U.S. patent application number 09/775716 was filed with the patent office on 2001-07-12 for method of manufacturing an enclosed transceiver.
Invention is credited to Lake, Rickie C., Tuttle, John R., Tuttle, Mark E..
Application Number | 20010007335 09/775716 |
Document ID | / |
Family ID | 27385062 |
Filed Date | 2001-07-12 |
United States Patent
Application |
20010007335 |
Kind Code |
A1 |
Tuttle, Mark E. ; et
al. |
July 12, 2001 |
Method of manufacturing an enclosed transceiver
Abstract
The present invention teaches a method of manufacturing an
enclosed transceiver, such as a radio frequency identification
("RFID") tag. Structurally, in one embodiment, the tag comprises an
integrated circuit (IC) chip, and an RF antenna mounted on a thin
film substrate powered by a thin film battery. A variety of antenna
geometries are compatible with the above tag construction. These
include monopole antennas, dipole antennas, dual dipole antennas, a
combination of dipole and loop antennas. Further, in another
embodiment, the antennas are positioned either within the plane of
the thin film battery or superjacent to the thin film battery.
Inventors: |
Tuttle, Mark E.; (Boise,
ID) ; Tuttle, John R.; (Boise, ID) ; Lake,
Rickie C.; (Eagle, ID) |
Correspondence
Address: |
WELLS ST JOHN ROBERTS GREGORY AND MATKIN
SUITE 1300
601 W FIRST AVENUE
SPOKANE
WA
992013828
|
Family ID: |
27385062 |
Appl. No.: |
09/775716 |
Filed: |
February 1, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09775716 |
Feb 1, 2001 |
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09008215 |
Jan 16, 1998 |
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6220516 |
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09008215 |
Jan 16, 1998 |
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08781107 |
Jan 9, 1997 |
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5776278 |
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08781107 |
Jan 9, 1997 |
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08602686 |
Feb 16, 1996 |
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08602686 |
Feb 16, 1996 |
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08137677 |
Oct 14, 1993 |
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08137677 |
Oct 14, 1993 |
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07899777 |
Jun 17, 1992 |
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Current U.S.
Class: |
235/492 |
Current CPC
Class: |
H01L 2924/01079
20130101; H04L 61/5046 20220501; H01L 2924/01047 20130101; H01L
24/24 20130101; G06K 19/07749 20130101; H01L 2924/30105 20130101;
H01L 2224/73267 20130101; G06K 19/07786 20130101; H01L 2224/24226
20130101; H01Q 1/38 20130101; G06K 19/0702 20130101; Y10T 29/49171
20150115; H01L 2224/32225 20130101; H01L 2924/01027 20130101; H01L
2924/014 20130101; H04L 61/35 20130101; G06K 19/073 20130101; H01L
2224/16 20130101; H01L 23/49855 20130101; H01L 2924/3011 20130101;
H01L 2224/24225 20130101; H01L 2924/01033 20130101; H01L 2224/24051
20130101; H04L 61/5084 20220501; Y10T 156/103 20150115; H01L
2224/2402 20130101; H01L 2924/01082 20130101; H01L 2924/3025
20130101; H01Q 1/2225 20130101; H01L 2924/01029 20130101; H04L
61/5092 20220501; H01Q 9/285 20130101; H01L 23/5389 20130101; H01Q
1/22 20130101; H04L 2101/604 20220501; H04L 2101/622 20220501; G01S
13/767 20130101; G06K 19/0723 20130101; H01Q 9/28 20130101; H04L
61/5038 20220501; G01S 13/758 20130101; H01L 24/82 20130101; H01L
2924/14 20130101; H01L 2224/73267 20130101; H01L 2224/32225
20130101; H01L 2224/73267 20130101; H01L 2224/32225 20130101; H01L
2224/24226 20130101; H01L 2924/00 20130101 |
Class at
Publication: |
235/492 |
International
Class: |
G06K 019/06 |
Claims
What is claimed is:
1. A method of manufacturing an enclosed device comprising the
steps of: providing a first film having a base portion and a cover
portion, the cover portion comprising a conductor; sealing the
cover portion to the base portion to encapsulate an integrated
circuit and a battery, wherein sealing electrically couples the
conductor, the integrated circuit, and the battery.
2. The method of claim 1 wherein the step of sealing comprises the
step of folding the cover portion onto the base portion.
3. The method of claim 1 wherein the integrated circuit comprises a
transceiver.
4. The method of claim 3 wherein the conductor is characterized by
an antenna geometry.
5. The method of claim 3 wherein a surface of the battery is
characterized by an antenna geometry.
6. The method of claim 1 further comprising the step of laminating
a plurality of layers to form the first film.
7. The method of claim 1 further comprising the step of coating a
polymer film with a barrier material to form the first film.
8. The method of claim 7 wherein the barrier material is a material
of the set consisting of silicon oxide, silicon nitride, a
fluorohalocarbon, and perchlorotetrafluoroethylene.
9. The method of claim 7 wherein the polymer film is polyester.
10. A method of manufacturing an enclosed device comprising the
steps of: providing a first film having an inner and an outer
surface; providing a second film having an inner and an outer
surface, the inner surface comprising a conductor; sealing the
second film to the first film to encapsulate an integrated circuit
and a battery between a portion of the inner surface of the first
film and a portion of the inner surface of the second film, wherein
sealing electrically couples the conductor, the integrated circuit,
and the battery.
11. The method of claim 10 further comprising the step of coating
at least one of the outer surface of the first film and the outer
surface of the second film with a material for preventing
contamination of the enclosed device.
12. The method of claim 10 further comprising the step of coating
the inner and outer surface of the first film and the inner and
outer surface of the second film with a material for preventing
contamination of the enclosed device.
13. The method of claim 10 wherein the material is a material of
the set consisting of silicon oxide, silicon nitride, a
fluorohalocarbon, and perchlorotetrafluoroethylene.
14. The method of claim 10 wherein the step of coating comprises a
process of the set consisting of sputtering, deposition,
evaporation, chemical vapor deposition, and plasma enhanced
chemical vapor deposition.
15. The method of claim 11 further comprising the step of applying
adhesive superjacent to the inner surface of the first film.
16. The method of claim 15 wherein the conductor is printed
superjacent to the adhesive.
17. The method of claim 16 wherein the shape of the conductor
comprises an aperture for exposing adhesive through the
aperture.
18. The method of claim 10 wherein the integrated circuit comprises
a transceiver for receiving a signal.
19. The method of claim 18 wherein the conductor is characterized
by an antenna geometry, the conductor conducts battery power to the
integrated circuit, and the conductor receives the signal.
20. The method of claim 10 wherein the step of sealing comprises:
pressing together the first film and the second film; and pressing
together a portion of the first film and a portion of the second
film, the portion of the first film and the portion of the second
film circmscribing at least one of the integrated circuit and the
battery.
21. A method of manufacturing an enclosed transceiver comprising
the steps of: preparing a first film from a first polymer film, the
first polymer film having a first inner side and a first outer
side, the step of preparing comprising: applying a first layer of
barrier material to the first inner side for reducing the porosity
of the first polymer film; applying a second layer of nonconductive
adhesive, the second layer covering a portion of the first layer;
and selectively applying a third layer of conductive adhesive to
form a first conductor on a portion of the second layer; preparing
a second film from a second polymer film, the second polymer film
having a second inner side and a second outer side, the step of
preparing comprising: applying a third layer of barrier material to
the second inner side for reducing the porosity of the second
polymer film; applying a fourth layer of nonconductive adhesive,
the fourth layer covering a portion of the third layer; and
selectively applying a fifth layer of conductive adhesive to form a
second conductor on a portion of the fourth layer; adhering an
integrated circuit transceiver and a battery to the first
conductor; and sealing the first film to the second film to
encapsulate the transceiver and the battery between a portion of
the first inner side and the second inner side, wherein sealing
electrically couples the second conductor to the transceiver
thereby powering the transceiver to receive a signal.
22. The method of claim 21 wherein the step of adhering the further
comprises the step of applying a second material superjacent to the
integrated circuit for stiffening, and exposing the second material
to ultraviolet radiation for curing the second material.
23. The method of claim 21 wherein a portion of the battery is
coupled to the integrated circuit for an antenna.
24. A method for testing a transceiver, the transceiver formed in a
sheet, the method comprising the steps of: pressing the sheet
between a first shield and a second shield, the first shield and
the second shield forming a cavity enclosing a transceiver, the
first shield comprising a test antenna; and receiving a signal
through the test antenna for determining the quality of the
transceiver.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This is a continuation-in-part of and claims priority from,
U.S. patent application Ser. No. 899,777 filed on Jun. 17,
1992.
TECHNICAL FIELD
[0002] The present invention relates generally to a process for
manufacturing an enclosed transceiver, such as a radio frequency
identification ("RFID") tag.
BACKGROUND
[0003] In the field of radio frequency identification ("RFID"),
communication systems have been developed utilizing relatively
large packages whose size is on the order of that of a cigarette
package or a substantial fraction thereof, and generally speaking,
have been fabricated using hybrid circuit fabrication techniques.
These relatively large electronic packages have been affixed, for
example, to railroad cars to reflect RF signals in order to monitor
the location and movement of such cars.
[0004] With respect to an enclosed electronic apparatus, a system
for handling baggage in an airport terminal is a typical
application. Such a system incorporates radio frequency
identification (RFID) between interrogators and transceivers.
Further, each baggage tag is an enclosed, battery operated
transceiver.
[0005] Other smaller passive RFID packages have been developed for
applications in the field of transportation, including the tracking
of automobiles. These packages include reflective systems of the
type produced by Amtech Inc. of Dallas, Tex. However, these
reflective passive RFID packages which operate by modulating the
impedance of an antenna are inefficient in operation, require large
amounts of power to operate, and have a limited data handling
capability.
[0006] In still other applications of article location and
tracking, such as in the postal service or in the field of airline
baggage handling and transport, it has not been practical or
feasible to use the above relatively large and expensive RFID
hybrid packages on smaller articles of transport such as letters,
boxed mail shipments or airline luggage. Accordingly, in these
latter areas of transport monitoring, as well as many other areas
such as inventory control of stored articles, article location and
tracking methods have traditionally employed bar code
identification and optical character recognition (OCR) techniques
which are well known in the art.
[0007] Bar code identification and OCR techniques are labor
intensive and may, for example, require several airline employees
or postal workers to physically manipulate the article and/or the
bar code readers to read these bar codes before the transported
article reaches its final destination. In addition, the cost of bar
code readers and optical character readers is high, limiting the
number of locations at which these readers can be used.
Furthermore, both bar code readers and optical character readers
tend to be highly unreliable.
[0008] In yet further and somewhat unrelated fields of: (1) animal
tracking and (2) plant tracking, other types of passive RFID tags
have been developed by Hughes/IDI/Destron of Irvine, Calif. These
tags utilize a coil wrapped around a ferrite core. Such passive
RFID tags have a very limited range, on the order of nine (9)
inches, have a very limited data handling capability, and are not
field programmable. In addition, these tags are limited in data
storage capacity and are slow in operation.
[0009] In view of the problems described above and related problems
that consequently become apparent to those skilled in the
applicable arts, the need remains for enclosed electronic apparatus
including transceivers wherein the enclosure is inexpensive,
readily manufactured in high volume, appropriate in size for use as
a stamp, label, or tag, and, in the case of transceivers, operable
over distances of several hundred feet without regard for the
spacial orientation of the enclosure.
SUMMARY
[0010] The general purpose and principal object of the present
invention is to provide a novel alternative approach to all of the
above prior art RFID, OCR, and bar code type location tracking and
data storage systems. This new approach as described and claimed
herein represents a fundamental breakthrough in the field of
article transport control in a wide variety of fields, of which the
fields of airline baggage transport, delivery of parcels and mail,
and inventory control are only three examples.
[0011] To accomplish this purpose and object, we have invented and
developed a new and improved radio frequency identification device,
an associated electrical system, and a method for communicating
with a remote RFID device from a local interrogator and controller.
The size of this new device will typically be on the order of one
inch square and 0.03 inches thick, or only slightly larger and
slightly thicker than a postage stamp. This device includes, in
combination, an integrated circuit (IC) which is mounted in an
approximately one inch square package and is encapsulated, for
example laminated, in a flexible or rigid thin film material. This
material may also include a suitable adhesive backing for reliably
securing the package to an outer surface or printed label of an
article of interest. The IC includes therein a receiver section for
driving suitable control logic and memory for decoding and staring
input information such as an identification number, the baggage
owner's name, point of origin, weight, size, route, destination,
and the like. This memory includes, but is not limited to, PROMS,
EPROMs, EEPROMs, SRAMS, DRAMs, and ferroelectric memory devices.
The IC also includes a transmitter section therein operative for
transmitting this information to an interrogator upon subsequent IC
interrogation. An RF antenna is placed in a desired geometrical
configuration (for example, monopole, dipole, loop, bow-tie, or
dual-dipole) and incorporated within or on the thin film material
and adjacent to the IC in an essentially two dimensional structure,
neglecting the approximately 30 mil thickness dimension of the
completed structure.
[0012] Advantageously, a thin battery is connected to the IC for
providing power to the IC. The IC also incorporates circuitry to
allow for operation in a sleep mode during transit and in storage
in order to conserve power. Thus, at shipment points of origin,
destination, and locations in transit, an operator may encode data
into the IC or interrogate the IC by signaling the IC from a remote
location to thereby "wake up" the IC without engaging in any
hands-on operation.
[0013] In a preferred embodiment of the invention, the integrated
circuit receiver and transmitter are operated in a spread spectrum
mode and in the frequency range of 200 Mhz to 10 GHz, with the
range of 800 MHz to 8 GHz being the range of most importance. This
operation has the effect of avoiding errors or improper operation
due to extraneous signal sources and other sources of interference,
multipathing, and reflected radiation from the surrounding
environment.
[0014] Accordingly, it is a further object of this invention to
provide an RFID electronic device of the type described and method
of fabricating such device.
[0015] Another object of this invention is to provide an RFID
system and method of operation of the type described which utilizes
RF transmitting and receiving sections on a single IC. Such a
system has applications for tracking people or articles in both
storage and transit.
[0016] Another object of this invention is to provide an electronic
device of the type described which does not include bulky hybrid
circuits, use modulation techniques described above for passive
RFID tags, nor require scanning of bar codes, bar code readers,
optical character readers, or especially clean operating
environments.
[0017] Another object of this invention is to provide an electronic
device of the type described which may be manufactured using
integrated circuit fabrication and packaging processes.
[0018] Another object of this invention is to provide an electronic
device of the type described which may be reliably and economically
manufactured at high yields and at a high performance to price
figure of merit.
[0019] Another object of this invention is to provide an RFID
device of the type described which is field writable and has a
transmission range greater than five (5) feet.
[0020] Another object of this invention is to provide a novel
assembly process for manufacturing the RFID electronic device
described herein.
[0021] Another object is to provide a manufacturing process of the
type described which is conducive to high speed automation.
[0022] Another object is to provide an enclosed electronic device
of the type described which is further conducive to high speed
product usage, since these RFID devices may be supplied to the
customer in a tape and reel format, a fan fold format, or a sheet
format.
[0023] Another object of this invention is to provide an RFID
device of the type described which may be powered with the use of
an RF coil and capacitor and without the use of a battery. Such
device is also referred to herein as the "passive" device
embodiment. However, the term "passive" refers only to the fact
that no battery is used, whereas the electrical circuitry on the IC
is indeed active while being powered by the RF coil and capacitor
combination.
[0024] Another object of this invention is to provide a non-contact
method of object and person detection and location which can serve
as a replacement for metal-to-metal contact in smart card
applications and as a replacement for magnetic strip, bar code, and
other types of contact-powered electronics. This novel method of
object detection and location represents a significant saving of
time and manual effort. For example, consider the time and effort
involved when a person must first remove a smart card from a pocket
or billfold and then insert the card in a card reader device before
being allowed entry into a secured area within a building.
[0025] Another object of this invention is to provide an electronic
device, system, and communication method of the type described
which represents, in novel combination, a fundamental breakthrough
in many diverse fields of article shipment, including the parcel
post and postal fields, the airline industry, inventory control for
many manufacturing industries, security, waste management,
personnel, and the like.
[0026] Accordingly, an enclosed electrical assembly of the present
invention includes a rigid or flexible thin film support member
having an integrated circuit (IC) disposed thereon and an antenna
incorporated within the IC or positioned adjacent to the IC within
a predetermined area of the thin support member; means on the IC
for receiving and encoding data relating to the article being
stored or shipped; and means on the IC for reading the stored data
and transmitting this data to an operator at a remote location.
[0027] According to a first aspect of such an assembly, a base
member and a cover member each having conductive patterns developed
thereon connect the IC in series with two thin film batteries. By
arranging two batteries with the IC, no substantial current flows
through a laminated or folded portion of the assembly. Smaller
signal levels, lower power operation, and longer useful life of the
assembly results.
[0028] According to another aspect, antenna coupling is also
provided to the IC without current flow through a laminated or
folded portion of the assembly. Greater sensitivity in receiving
and lower losses in transmitting result.
[0029] According to another aspect of the present invention, an
RFID device has two modes of operation are provided with a wake-up
circuit. The wake-up circuit senses in-band energy and switches
from a sleep mode to an operating (waked) mode. The sleep mode
being useful during transit and storage of the RFID device to
conserve battery power.
[0030] According to another aspect of such an RFID device, the IC
includes receiver and transmitter sections characterized by spread
spectrum modulation. Use of spread spectrum modulation reduces data
transmission and reception errors, reduces the possibility of
improper operation in response to extraneous signal sources,
reflected radiation from a surrounding noisy environment, and other
interference. Battery power is thereby conserved.
[0031] According to another aspect of the present invention, the
enclosure includes an adhesive on an outer surface thereof. The
adhesive permits reliable and convenient securing of a device of
the present invention to an article being transported or
stored.
[0032] According to yet another aspect of the present invention, by
enclosing a transceiver in film, an extremely light weight,
durable, and thin package results. Such a package is appropriate
for use in replacement of or in conjunction with the conventional
handwritten label, conventional hand-cancelled or postage-metered
stamp, and the conventional baggage tag.
[0033] According to another aspect of the present invention, the
frequencies of radio communication, modulation scheme, geometry of
the antenna, capacity of the battery, and electrical properties of
the enclosure cooperate for omnidirectional communication between
an enclosed transceiver of the present invention and a distant
interrogator. No manual manipulation of the interrogator or
transceiver is required for area-wide communication such as
confirming the contents of a delivery vehicle or verifying
inventory in place, to name a few examples.
[0034] According to an aspect of another embodiment of the present
invention, a plurality of transceivers are enclosed and laminated
between a pair of films. One side of one of the films has adhesive
capability. The transceivers are separated and arranged on a
backing. A roll or tape of the backing having transceivers
removably attached thereto is enclosed in an RF tight dispenser.
The dispenser provides convenient access to unprogrammed
transceivers for use on articles to be shipped. When removed from
the dispenser, a transceiver communicates with an interrogator in
the area for establishing transceiver identity, shipping
authorization, destination or storage criteria, date of issue, and
similar information. By shielding transceivers within the dispenser
from wake-up signals, battery power is conserved.
[0035] These and other embodiments, aspects, advantages, and
features of the present invention will be set forth in part in the
description which follows, and in part will become apparent to
those skilled in the art by reference to the following description
of the invention and referenced drawings or by practice of the
invention. The aspects, advantages, and features of the invention
are realized and attained by means of the instrumentalities,
procedures, and combinations particularly pointed out in the
appended claims.
DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1A and FIG. 1B are functional block diagrams of
enclosed transceivers of the present invention.
[0037] FIG. 2 is a perspective view of an enclosed transceiver as
shown in FIG. 1A.
[0038] FIG. 3 is a plan view showing the conductive patterns on the
base and cover members used in FIG. 2, including dotted line
outlines of the locations for the IC and batteries.
[0039] FIG. 4A through FIG. 4D are cross sectional views taken
along lines 4-4 of FIG. 3 showing four processing steps used in
constructing the enclosed transceiver shown in FIG. 3.
[0040] FIG. 5A is a perspective view of an alternate embodiment of
the invention wherein the IC is mounted on a parallel plate
capacitor which in turn is mounted on a battery.
[0041] FIG. 5B is an enlarged portion of FIG. 5A.
[0042] FIG. 6A through FIG. 6E are cross sectional views taken
along lines 6-6 of FIG. 5 showing five processing steps used in
constructing the embodiment shown in FIG. 5.
[0043] FIG. 7 is a cross-sectional view showing an arrangement of
battery and capacitor alternate to the embodiment shown in FIG.
5.
[0044] FIG. 8 is a perspective view of another alternate embodiment
of the present invention having battery surfaces defining and
performing the function of a bow-tie antenna.
[0045] FIG. 9 shows an alternate, passive device embodiment of the
present invention in partially cut-away perspective view wherein
the battery has been altogether eliminated and further wherein a
capacitor is periodically charged from an external source in a
manner described below to provide operating power to the IC.
[0046] FIG. 10 is a top view of a web of enclosed transceivers of
the present invention.
[0047] FIG. 11 is an exploded perspective view of the top and
bottom films used to construct one of the enclosed transceivers
shown in FIG. 10.
[0048] FIG. 12 is a cross-sectional view taken along lines 12-12 of
FIG. 11 showing a portion of the web shown in FIG. 10 and
illustrating electrical coupling to and between the films.
[0049] FIG. 13A is a process flow diagram showing the steps of the
present invention used to manufacture an enclosed transceiver.
[0050] FIG. 13B is a process flow diagram showing the steps of the
present invention used to manufacture another enclosed
transceiver.
[0051] In each functional block diagram, a single line between
functional blocks represents one or more signals. A person of
ordinary skill in the art will recognize that portions of the
perspective views and cross-sectional views are enlarged for
clarity.
DESCRIPTION
[0052] FIG. 1A and FIG. 1B are functional block diagrams of
enclosed transceivers of the present invention. Enclosed
transceiver 1 includes a pair of batteries 2 and 3, a dipole
antenna 4 and 5, and an integrated circuit (IC) 11. Batteries 2 and
3 are in series connection through line 6 and cooperate as powering
means for supplying power to IC 11 through lines 8 and 9. As will
be discussed below, the series connection of two batteries
simplifies conductor patterns in the enclosure. IC 11 is a four
terminal device operating as communicating means for transmitting
and receiving radio signals. Dipole antenna 4 and 5 couples radio
signals between IC 11 and the communications medium which separates
enclosed transceiver 11 from an interrogator, not shown. The
interrogator is located up to 400 feet from enclosed transceiver
11.
[0053] Integrated circuit 11 is a transceiver including wake-up
circuit 12, receiver 13, transmitter 14, control logic 15, and
memory 16. Each of these functional circuits receives power signals
VCC and GND on lines 8 and 9. When a received signal has
substantial in-band energy as detected by wake-up circuit 12,
control logic 15 enables receiver 13 for receiving and decoding a
radio signal on antenna 4 and 5. Received data is provided by
receiver 13 to control logic 15. Control logic 15 writes received
data into memory 16. Control logic 15 also processes (i.e. decodes,
tests, or edits) the received data with data stored in memory 16
and determines whether a response transmission is appropriate and
the content of such a response. If a response is appropriate,
control logic 15 reads transmit data from memory 16 and enables
transmitter 14 for sending the transmit data as a second radio
signal on antenna 4 and 5. Control logic 15 operates as a
controller for reading data from and writing data to memory 16.
Antenna 4 and 5 matches the medium to the receiver and to the
transmitter for improved receiver sensitivity, and reduced
transmission losses. Dipole antenna 4 and 5 has a toroidal antenna
pattern with a null along the axis of the toroid.
[0054] FIG. 1B is a functional block diagram of an alternate
enclosed transceiver of the present invention. Like numbered
elements correspond to elements already described with reference to
FIG. 1A. Enclosed transceiver 18 includes loop antenna 19, battery
20, and integrated circuit 21. Loop antenna 19 provides near
omnidirectional communication capability as will be discussed with
reference to FIG. 11.
[0055] Battery 20 is connected to antenna line 22 to reduce the
number of terminals required to connect integrated circuit 21 into
enclosed transceiver 18 and to improve the omnidirectional nature
of the antenna pattern. A novel enclosure implements this
connection to be discussed below. Integrated circuit 21 is a three
terminal device providing the same functions as integrated circuit
11 already described with reference to FIG. 1A.
[0056] As an example of a data call-up operation, consider the
events surrounding checking baggage or mailing a package. When an
enclosed transceiver of the present invention is placed on the
outside surface of a piece of luggage by the airlines or on a
package for shipment by the postal service, an airline agent or
postal worker operates an interrogator. The interrogator transmits
information to receiver 13 via an RF communication link concerning
data such as the owner's name, an ID number, point of origin,
weight, size, route, destination, amount of postage prepaid,
billing information for debit, postage, handling, or storage costs
due, time stamp, and the like. This received data is coupled to
control logic 15 for processing, encoding, and storage in memory
16. Stored data is made available for call up by an interrogator at
one or more points along the shipment route.
[0057] For example, upon reaching a point of shipment destination,
an interrogator calls up stored data and uses it at the point of
destination for insuring that the item of luggage or shipment is
most assuredly and efficiently put in the hands of the desired
receiver at the earliest possible time. Specifically, an
interrogator at the destination point sends interrogation signals
to the enclosed transceiver 1 where they are received by antenna 4
and 5 and first processed by sleep/wake up circuit 12. Wake-up
circuit 12 operates to bring integrated circuit 11 out of a "sleep"
made into a "waked" mode wherein receiver 13 receives and decodes
signals to provide received data to control logic 15.
[0058] With integrated. circuit 11 now in "waked" mode, memory 16
is read by control logic 15 to call-up transmit data, i.e. the
above six pieces of information relating to the shipped article.
Control logic 15 then couples the transmit data to transmitter 14
and enables transmitter 14 for sending transmit data to the
interrogator.
[0059] Receiver 13 and transmitter 14 preferably employ one of the
well known spread spectrum modulation techniques including for
example: (1) direct sequencing, (2) frequency hopping, (3) pulsed
FM or chirped modulation, (4) time hopping, or (5) time-frequency
hopping used with pulse amplitude modulation, simple amplitude
modulation or binary phase shift keying.
[0060] The communication circuitry of an interrogator (not shown)
is designed to conform to the modulation technique, message
encoding, and modes of operation described for the enclosed
transceivers of the present invention. Interrogator design is
understood by those skilled in the art and, therefore, is not
described herein.
[0061] FIG. 2 is a perspective view of an enclosed transceiver as
shown in FIG. 1A. Enclosed transceiver 1 includes a base support
layer 30 upon which an integrated circuit 32 is disposed on the
near end of layer 30 and connected to a dipole antenna consisting
of a pair of conductive strips 34 and 36 extending laterally from
IC 32. These conductive strips 34 and 36 will typically be screen
printed on the upper surface of base support layer 30.
[0062] A pair of rectangularly shaped batteries 38 and 40 are
positioned as shown adjacent to IC 32 and are also disposed on the
upper surface of base support member 30. Rectangular batteries 38
and 40 are electrically connected in series to power IC 32 in a
manner more particularly described below. Assembly of enclosed
transceiver 1 is completed by the folding over of an outer or upper
cover member 42 which is sealed to the exposed edge surface
portions of the base member 30 to thereby provide an hermetically
sealed and completed package. When cover member 42 is folded over
onto base member 30, conductive strip 50 is attached to batteries
38 and 40 using conductive epoxy. Conductive strip 50 provides
means for coupling a pole of battery 38 to a pole of battery 40;
thus accomplishing the series electrical connection of batteries 38
and 40. Integrated circuit 32 has transmitter, memory, control
logic, and receiver stages therein and is powered by batteries 38
and 40 during the transmission and reception of data to and from an
interrogator to provide the interrogator with the various above
information and identification parameters concerning the article,
animal or person to which the enclosed transceiver is attached.
[0063] FIG. 3 is a plan view showing the conductive patterns on the
base and cover members used in FIG. 2, including dotted line
outlines of the locations for the IC and batteries. During the
initial manufacturing stage for the enclosed transceiver, base 30
and cover 42 are joined at an intersecting line 44. Dipole antenna
strips 34 and 36 are shown positioned on each side of IC 32. Two
conductive strips 46 and 48 serve to connect the bottoms of
batteries 38 and 40 to IC 32. Conductive strip 50 is provided on
the upwardly facing inside surface of top cover 42, so that, when
cover 42 is folded at intersecting line 44, the outer boundary 52
of cover 42 is ready to be sealed with the outer boundary 54 of
base support member 30. Simultaneously, conductive strip 50 bonded
by the conductive epoxy to batteries 38 and 40, completes the
series electrical connection used to connect batteries 38 and 40 in
series with each other and further in series circuit with
integrated circuit 32 through conductive strips 46 and 48.
[0064] FIG. 4A through FIG. 4D are cross sectional views taken
along lines 4-4 of FIG. 3 showing four processing steps used in
constructing the enclosed transceiver shown in FIG. 3. FIG. 4A
shows in cross sectional view IC 32 bonded to base support member
30 by means of a spot or button of conductive epoxy material 56.
Conductive strip 48 is shown in cross section on the upper surface
of base support member 30.
[0065] In FIG. 4B, battery 40 is aligned in place as indicated
earlier in FIG. 2 and has the right hand end thereof bonded and
connected to the upper surface of conductive strip 48 by means of a
spot of conductive epoxy applied to the upper surface of conductive
strip 48, but not numbered in this figure.
[0066] In FIG. 4C, a stiffener material 58 is applied as shown over
the upper and side surfaces of IC 32. The stiffener material will
preferably be an insulating material such as "glob-top" epoxy to
provide a desired degree of stiffness to the package as completed.
Next, a spot of conductive epoxy is applied to each end of
conductive strip 50, and then cover layer material 42 with the
conductive epoxy thereon is folded over onto batteries 38 and 40
and base member 30 to cure and heat seal and, thus, complete and
seal the package in the configuration shown in FIG. 4D.
[0067] FIG. 5A is a perspective view of an alternate embodiment of
the invention wherein the IC is mounted on a parallel plate
capacitor which in turn is mounted on a battery. FIG. 5B is an
enlarged portion of FIG. 5A. The enclosed transceiver shown
includes the combination of battery 60, capacitor 62, and IC 64.
When inrush current requirements for IC 64 exceed the capability of
battery 60 to supply surge current, for example, due to inductive
coupling or battery structure, inrush current is supplied by
capacitor 62. The structure of battery 60 is in direct contact with
the upper surface 66 of a base support member 68. The structure of
parallel plate capacitor 62 is positioned intermediate to the upper
surface of the structure of battery 60 and the bottom surface of IC
64. In order to facilitate making electrical contacts to capacitor
62 and battery 60, respectively, an exposed capacitor bottom plate
area 65 is provided on the left hand side of this structure and an
exposed battery bottom plate area 67 is provided on the right hand
side of the battery-capacitor-chip structure. A plurality of
antenna lines 70, 72, 74, and 76 form two dipole antennas connected
to opposite corners of IC 64 in a generally X-shaped configuration
and extend as shown from IC 64 to the four corners of the package.
Upper polymer cover 77 is sealed in place as shown to hermetically
seal all of the previously identified elements of the package
between base support member 68 and polymer cover 77.
[0068] FIG. 6A through FIG. 6E are cross sectional views taken
along lines 6-6 of FIG. 5 showing five processing steps used in
constructing the embodiment shown in FIG. 5. Base starting material
includes a first or base polymer layer 78, such as polyester or
polyethylene, which is laminated with a relatively impermeable
material such as metal film, PVDC, or silicon nitride. Base layer
78 is coated on the bottom surface thereof with a suitable adhesive
film 80 which will be used for the device adhesion during device
usage. If the adhesive is sufficiently impermeable, the impermeable
coating may be omitted. The battery connection and attachment are
made on the upper surface of base layer 78 using a spot of
conductive epoxy. Conductive epoxy is also used at interface 94
between battery 60 and capacitor 62 and interface 98 between
capacitor 62 and IC 64.
[0069] Referring now to FIG. 6B, a thin film battery consisting of
parallel plates 84 and 86 is placed on base layer 78. Next, a
capacitor comprising parallel plates 90 and 92 is attached onto
battery layer 84 using a conductive epoxy. Bottom plate 92 of
capacitor 62 is somewhat larger in lateral extent than ton
capacitor plate 90 in order to facilitate the necessary electrical
connection of battery 60 and capacitor 62 to integrated circuit 96.
IC 96 corresponds to IC 64 in FIGS. 5A and 5B. IC 96 is then
attached to top capacitor plate 90 with a conductive epoxy at
interface 98, thereby providing an electrical connection. The
bottom surface of IC 96 is metallized to facilitate this
connection. In an alternate and equivalent fabrication process, an
epoxy cure heat step or metallization anneal step is used to
enhance the sealing between the various above stacked elements.
[0070] Referring now to FIG. 6C, prefabricated insulating layer 100
is now laid over the battery/capacitor/IC stack in the geometry
shown. Layer 100 includes openings 102, 104, 110, and 112 therein
for receiving a conductive polymer material as will be described
below in the following stage of the process. Prefabricated holes
102, 104, 110, and 112 in layer 100 are aligned, respectively, to
the battery contact, to the capacitor contact, and to the contacts
on the top of IC 96. Layer 100 is then sealed to base polymer layer
78 using, for example, a conventional heating or adhesive step.
[0071] Referring now to FIG. 6D, a conductive polymer material 108
is deposited in openings 102 and 104 in the lower regions of layer
100 and extended up into the upper openings 110 and 112 of layer
100 to make electrical contact as indicated on the upper surface of
IC 96. The shaped conductive epoxy material 108 may also be
preformed utilizing a stamping tool or silk screening techniques
and is applied as shown over the upper surface of layer 100.
Conductive epoxy material 108 forms the innermost region of the
antenna structure extending from IC 96 out in the dual dipole
geometry as previously described with reference to FIGS. 5A and 5B.
However, the complete antenna geometry shown in FIG. 5A is outside
the lateral bounds of the fragmented cross sectional views shown in
FIGS. 6A through 6E. At this point in the process, an epoxy cure
heat step is optional.
[0072] Referring now to FIG. 5, polymer insulating layer 114 is
formed on the upper surface of layer 100 in the geometry shown and
further extends over the exposed upper surfaces of the conductive
epoxy polymer antenna material 108. Layer 114 is then sealed to
layer 100 using either heat or adhesive sealing. Layer 114 provides
a final hermetic seal for the completed device shown in cross
section in FIG. 6E.
[0073] FIG. 7 is a cross-sectional view showing an arrangement of
battery and capacitor alternate to the embodiment shown in FIG. 5.
As shown in FIG. 7, the battery and capacitor are mounted
side-by-side under the IC. The electrical connection for battery
118 and capacitor 120 to integrated circuit 96 is provided by
positioning the battery 118 and capacitor 120 in the co-planar
configuration shown on the surface of base polymer layer 78. The
bottom plate of battery 118 is connected through conductive epoxy
layer 128 to the top surface of IC 96. The bottom plate of parallel
plate capacitor 120 is connected through conductive epoxy layer 128
to the top surface of the IC 96. A small space 126 is provided as
shown to electrically isolate battery 118 and capacitor 120. In
addition, in this embodiment of the invention, conductive material
128 is extended as shown between the left side opening 130 in the
layer 100 and a lower opening 132 in layer 100. In a manner similar
to that described above with reference to FIGS. 6A through 6E,
layer 114 is then extended over the top surface of layer 100 in the
geometry shown. Conductive polymer material 128 extends to connect
the crossed antenna structure of FIG. 5 to IC 96 shown in FIG.
7.
[0074] FIG. 8 is a perspective view of another alternate embodiment
of the present invention having battery surfaces defining and
performing the function of a bow-tie antenna. IC 138 is centrally
positioned as shown on the upper surface of base support member 140
and is electrically connected to two triangularly shaped batteries
142 and 144, also disposed on the upper surface of base support
member 140. Batteries 142 and 144 are connected in series with IC
138 when protective cover member 146 is sealed over the top
surfaces of the two batteries 142 and 144 and the IC 138 using
processing steps previously described.
[0075] In the embodiment of the invention shown in FIG. 8, the
entire outer surfaces of the two batteries 142 and 144 serve as a
"bow tie" antenna structure for the enclosed transceiver. At
communication wavelengths, the top and bottom surfaces of batteries
142 and 144 are coupled together. Batteries 142 and 144 are
connected in series with the IC 138 to provide DC operating power
therefor in a manner previously described. Moreover, the dual use
of the batteries as power supplies and antenna structures minimizes
the number of terminals required to connect IC 138 into an enclosed
transceiver.
[0076] FIG. 9 shows an alternate, passive device embodiment of the
present invention in partially cut-away perspective view wherein
the battery has been altogether eliminated and further wherein a
capacitor is periodically charged from an external source in a
manner described below to provide operating power to the IC. This
embodiment is known as the passive or battery-less device
embodiment, since it contains no battery therein. Instead,
operating power is provided by a capacitor structure identified as
component 148 located beneath IC 150. A charge on capacitor 148 is
maintained by conventional RF charging circuits (not shown) on IC
150 which are energized from a remote source.
[0077] The enclosed transceiver shown in FIG. 9 includes a first
loop antenna 152 for receiving RF charging signals for capacitor
148 and a dipole antenna formed of conductive strips 154 and 156
for receiving and transmitting data to and from IC 150. As in
previous embodiments, capacitor 148 and IC 150 are positioned and
hermetically sealed between a base cover member 157 and a top cover
member 158.
[0078] FIG. 10 is a top view of a web of enclosed transceivers of
the present invention. Laminated sheet 200 includes 36 enclosed
transceivers 210 simultaneously manufactured in a plurality of
cavities as already described. Sheet 200 in a preferred embodiment
includes 252 enclosed transceivers, each approximately 1.5 inches
square. Alternatively, sheet 200 includes one folded film as
illustrated in FIGS. 2, 3, and 4; three coextensive films 114, 100,
and 78 as illustrated in FIGS. 6 and 7; or two coextensive films as
is apparent from FIGS. 8 and 9, and FIGS. 11 and 12 to be discussed
below. Sheet 200, in one embodiment is sectioned to obtain
individual enclosed transceivers by interstitial cutting,
perforation and tearing, or sheering; sectioning being simultaneous
with or following the step of sealing each enclosed cavity by
lamination, embossing, hot stamping or the like. Alternatively
enclosed transceivers are manufactured in a continuous strip, for
example, one enclosure.
[0079] After manufacturing has been completed, a large number of
finished devices, or webs are stored on a take-up reel (not shown)
supporting a corresponding large plurality of the devices.
Advantageously, storage on a take-up reel not only makes the
present process conducive to high speed automated manufacturing,
but in addition makes the process compatible to high speed manual
or automated product dispensing and use. Large numbers of enclosed
transceivers may be supplied easily to a user in a conventional
tape and reel format. The user can readily detatch one device at a
time for immediate attaching to an article. Alternatively, enclosed
transceivers are manufactured and shipped in sheets and later
sectioned by the customer.
[0080] In yet another embodiment, devices are cut from the tape or
sheet from which they were manufactured and then removably mounted
on a backing. The backing in one embodiment is in tape format and
in another equivalent embodiment is in sheet format. When mounted
to a backing, enclosed transceivers are more effectively stored in
a cache for dispensing individually. The cache, not shown, includes
means for dispensing (i.e. separately providing a transceiver on
demand) and shielding means for preventing signal reception by
enclosed transceivers within the cache. If shielding were not
included, a supply of transceivers located within communicating
range of an interrogator would soon expend battery capacity by
processing signals including, for example, wake-up signals. Means
for dispensing includes, for example, mechanical devices for
feeding a tape or sheet through an opening and mechanical devices
for separating shielding materials from a tape or sheet. The former
dispensing means, in one embodiment of the cache, cooperates with
shielding across the opening including conductive rollers,
separating brushes, separating fingers, and the like. The latter
dispensing means, in another embodiment of the cache, cooperates
with conductive backing material, or conductive foam as a backing
or cover layer arranged to shield the exposed edges of a roll
containing transceivers.
[0081] FIG. 11 is an exploded perspective view of the top and
bottom films used to construct one of the enclosed transceivers
shown in FIG. 10. The embodiment shown corresponds to enclosed
transceiver 18 shown in FIG. 1B. Top film 214 includes area 222 for
lamination onto the top surface (pole) of battery 20; strip 218 for
loop antenna 19; and, contact area 226. Each of these three
features, in a preferred embodiment, is formed of conductive ink.
In an alternate and equivalent embodiment, these three features are
formed of conductive epoxy. Bottom film 230 includes area 238 for
lamination onto the bottom surface (pole) of battery 20; strip 234
for loop antenna 19; contact area 254; and contact points 242, 246,
and 250 for connecting integrated circuit 21 to the battery and
antenna. Each of these six features, in a preferred embodiment, is
formed of conductive ink, though conductive epoxy is
equivalent.
[0082] Contact 246 is intentionally misaligned with respect to area
222 to prevent shorting battery 20. However, strips 218 and 234 are
aligned to coincide, as are contact areas 226 and 254,
respectively. These strips and contact areas when joined by
lamination cooperate as means for coupling power from battery 20 to
IC 21 and, simultaneously, for electrically matching IC 21 to the
communications medium by forming loop antenna 19. Thus, contacts
242, 246, and 250 correspond respectively to lines 24, 23, and 22
shown in FIG. 1B.
[0083] Unlike the antenna pattern of the dipole antenna shown in
FIGS. 1A, 2, 3, and 9, there is no null in the antenna pattern for
loop antenna 19, due in part to the conductive structure of battery
20 being connected to one side of loop antenna 19. The combined
loop antenna and battery structure is also preferred over the
dipole in that the combination provides an antenna pattern that is
less subject to variation over a broad range of frequencies.
[0084] FIG. 12 is a cross-sectional view taken along lines 12-12 of
FIG. 11 showing a portion of the web shown in FIG. 10 and
illustrating electrical coupling to and between the films. The
completed assembly includes similarly numbered elements already
discussed with reference to FIG. 11. IC 390 is prepared for
assembly by forming conductive bumps 306 and 314 to terminals on
its lower surface. In a preferred embodiment, bumps are formed of
conductive epoxy. In an alternate embodiment, metallic bumps, such
as gold, are formed by conventional integrated circuit processes.
IC 390 as shown is in a "flip chip" packaging orientation having
substantially all circuitry formed on the surface facing film 230.
Prior to assembly, a puddle of conductive epoxy is applied to
contacts 250 and 242. IC 390 is then located atop contacts 250 and
242 so that bumps 306 and 314 are surrounded within puddles 302 and
310. The film is then heated to set all conductive epoxy including
puddles 302 and 310, as well as strips and areas including the
antenna and contact areas 226 and 254, formed of conductive epoxy.
Finally, top film 214 is aligned over bottom film 230 so that
contact areas 226 and 254 are pressed together.
[0085] FIG. 13A is a process flow diagram showing the steps of the
present invention used to manufacture an enclosed transceiver of
the type shown in FIGS. 10-12. The manufacturing process begins
with a polyester film used for the bottom and for the top. Material
for the bottom in a first embodiment is identical to the top and
includes film with dimensional stability, for example, polyester
film that has been heat stabilized or pre-shrunk. These materials,
though inexpensive, are porous to substances that degrade the life
and functions of the battery and integrated circuit. This
disadvantage is resolved in a preferred embodiment by coating the
outer surfaces of the material used for the top and bottom film
with a barrier material
[0086] In the first step 410, barrier material, such as a silicon
nitride deposit, is formed on the outer surface by sputtering, or
by chemical vapor deposition (CVD), preferably plasma enhanced CVD.
The deposit provides a hermetic barrier to prevent water vapor and
other contaminants from affecting (e.g. oxidizing) battery and
transceiver components. In a first embodiment the resulting
thickness of the deposit is from 400 to 10,000 angstroms. In
another embodiment, where thin deposits are desirable, coating on
both sides of the film prevents pin holes in each deposit from
aligning in a way that defeats hermeticity. The thickness of the
deposit and the manner of formation are design choices based on the
selection of materials for the film and the deposit, as well as the
system requirements for hermeticity over time. For example an
alternate and equivalent embodiment uses other barrier materials
including silicon oxide and silicon nitride deposited at a
thickness of 100 to 400 angstroms. The barrier material is formed
in such an embodiment using one of the processes including
evaporation, deposition, chemical vapor deposition, and plasma
enhanced chemical vapor deposition.
[0087] In another embodiment of the present invention, a nitride
film is sputtered on the outside portion of a top and bottom base
support layer. Each base support layer preferably comprises a
polymer material such as a polyester film that is laminated with a
barrier layer material such as polyethylene and/or polyvinylidene
chloride (PVDC). Formation of the barrier material deposit can be
deferred until the enclosed transceiver is encapsulated, provided
that environmental concerns such as contamination, over heating,
and changes in pressure are addressed.
[0088] In step 420, a laminate adhesive is applied to the inner
surfaces of the top and bottom films. The laminate adhesive is
activated in a later manufacturing step to cause the top and bottom
layers to adhere. Preferably, the adhesive is tack free at room
temperature and selected to match laminating equipment heat and
pressure capabilities. In a preferred embodiment, butyl acrylate is
extruded onto the films to cover the entire inside surface of each
film. In another embodiment, the adhesive is screen printed for
economy.
[0089] In step 430, conductors are screen printed onto the films.
In a preferred embodiment, the conductors are formed on top of
laminate adhesive. Areas such as grid conductors 222 and 238 shown
in FIG. 11 for contacting the battery are, consequently,
interspersed with areas of exposed laminate adhesive to provide a
more durable enclosure. In this embodiment, a polymer thick film
ink is employed. High conductivity is provided by such inks that
include copper or silver constituents. The ink preferably provides
a stable surface for electrical butt contact formations. A low
oxidation rate at storage temperature is desirable, though
oxidation could be minimal in a controlled manufacturing
environment.
[0090] Printed circuits on the top layer are arranged to perform
multiple functions when the top and bottom layers are joined.
First, a conductor on the top layer completes series or parallel
circuits for devices having contacts in two planes. Conductor 50 in
FIG. 2 is one example. Second, a conductor on the top layer
completes an antenna structure for the transceiver integrated
circuit, as illustrated in FIG. 8. Third, a single conductor in the
top layer accomplishes both the first and second functions. See,
for example, the conductor in FIG. 11 identified as areas 226, 222,
and 216.
[0091] In an alternate embodiment, conductors are formed in a
subtractive process, for example, chemical etching. By using a
positive screen print process, energy and material are conserved.
Printed circuit technology is applied in another embodiment wherein
the step of attaching the integrated circuit and the battery to a
base material includes soldering and brazing. The base material in
such an embodiment is one of a wide variety of printed circuit
materials including polyimide and glass-epoxy materials.
[0092] In step 440, the top and bottom base support layers are cut
from the roll or web to form sheets as illustrated in FIG. 10 to
facilitate use of automated component placement machinery. Each
sheet is attached, in step 450, to a carrier panel for
compatibility with conveyor based manufacturing facilities. At step
460, a carrier with sheet attached is loaded into a magazine or
placed onto a conveyor for automated manufacturing. Steps 440-460,
in an alternate embodiment of the manufacturing process of the
present invention, are omitted as unnecessary when continuous
manufacturing from roll stock is desirable.
[0093] In step 470, those portions of conductors that are to make
electrical contact with the integrated circuit are prepared with a
coating or puddle of conductive epoxy. In a preferred embodiment,
silver filled epoxy is employed that remains wet at room
temperature until thermally cured. Application of the epoxy is by
screen printing. In an alternate embodiment, epoxy is applied by
dispensing.
[0094] In step 480, integrated circuit die are placed so that epoxy
bumps previously formed on the integrated circuit enter the puddles
formed in step seven. The arrangement of the integrated circuit
face down on the bottom film is commonly referred to as "flip-chip"
orientation. In an alternate and equivalent embodiment, integrated
circuits are also placed in contact puddles formed on the top, i.e.
cover layer. All die on the sheet are placed and aligned in this
step 480 prior to proceeding with subsequent cure.
[0095] In step 490, a batch of panels is heated to set the epoxy
applied in step seven. In an alternate embodiment, a conveyor based
oven supports continuous curing. Curing temperature and duration
are design choices that match the epoxy curing requirements. In a
preferred embodiment, curing is performed at 150 degrees Celsius
for 3 to 5 minutes. The cure is selected so as not to interfere
with the characteristics of the laminate adhesive applied in step
420.
[0096] In step 500, an encapsulation material, commonly called
"glob top epoxy" is applied over the integrated circuit. Suitable
nonconductive materials include those providing a stiffening
property to protect the integrated circuit and the electrical
connections thereto from mechanical damage.
[0097] In step 510, the encapsulating material is cured. In a
preferred embodiment, the encapsulating material is cured with
ultraviolet radiation. An alternate and equivalent embodiment,
employs a thermal curing process. The ultraviolet cure is preferred
for rapid manufacturing. However, use of a thermal cure in step 510
may permit use of a partial thermal cure in step 490, later
perfected by additional thermal cure duration provided in step
510.
[0098] In step 520, the battery or batteries are aligned and placed
on the base support film. In an embodiment including stacked
battery cells, connection is made using conductive tape having
adhesive on both sides of the tape. Such tape commonly includes
conductive particles in the adhesive.
[0099] In step 530, the top or cover film is aligned over the
bottom or base film. In an embodiment including a folded film, the
top film is folded over the base film. In an alternate embodiment
employing continuous manufacturing from roll stock, the base film
and top film are aligned for continuous lamination.
[0100] In step 540, the top cover film is pressed onto the bottom
base film and heat is applied to activate the adhesive applied in
step 420. For butyl acrylate adhesive a temperature of from 95 to
110 degrees Celsius is preferred.
[0101] In applications where the transceiver is to be used in harsh
environments, the seal provided by automated lamination equipment
may be incomplete or have weaknesses caused, for example, by
insufficient heat or pressure at a point in an area to be sealed.
Enclosing components of varying thicknesses can result in air
pockets surrounding such components that, if too near the
periphery, can also lead to weaknesses and voids. In such
applications, the preferred process includes step 550 wherein the
periphery of each transceiver on a sheet is subject to a second
application of heat and pressure for activating laminate adhesive
applied in step 420. The additional heat and pressure in such a
localized periphery can deform the films to form minute bosses.
Thus, the step is called embossing. The aspect of the effective
application of heat and pressure is more important than the extent
of consequential deformation.
[0102] In an alternate embodiment, each enclosure is evacuated.
Lamination for such an embodiment is conducted in an evacuated
environment. Embossing in yet another embodiment is also conducted
in an evacuated environment.
[0103] After step 540, the circuitry of the battery powered
transceiver is active by virtue of the completed circuits formed
when the top cover layer is aligned and butt contacts are formed
with components and the base layer. Functional tests of multiple or
individual transceivers are now feasible.
[0104] In step 560, transceivers are functionally tested. To
prevent interference between tests of individual transceivers, a
pair of grounded plates with surface features are placed on both
sides of a sheet of enclosed transceivers so that each transceiver
operates inside a shielded cavity. The wavelength used for testing
is selected such that leakage through the thickness of the embossed
seal is negligible. Plates similar to the embossing die used in
step 550 are used in one embodiment. Each cavity includes an
antenna for transmitting stimulus signals and for receiving
response signals for measuring the quality of each transceiver.
Measurements include, for example, receiver sensitivity,
transmitted spectrum, message handling capability, self-testing,
and response timing.
[0105] In step 570, the sheet of tested transceivers is sheered in
two dimensions to singulate or separate the transceivers from one
another. In an alternate and equivalent embodiment, a backing
material is applied to one side of the sheet prior to singulation.
Singulation for this embodiment is accomplished by kiss cutting
through the top and base films leaving the transceivers attached to
the backing material. Transceivers, whether attached to the backing
or loose are then sorted based on the results of functional testing
performed in step 560 and additional testing as needed.
[0106] FIG. 13B is a process flow diagram showing the steps of the
present invention used to manufacture another enclosed transceiver
of the types shown in FIGS. 2-9. This embodiment of the method of
the present invention includes nine (9) processing steps or
fabrication stages which are used in the overall manufacturing
process and in the construction of an enclosed transceiver.
[0107] In one embodiment the nine steps are performed sequentially
as follows. In step 610, a circuit pattern is initially formed on a
base layer material. This base layer material is preferably a
polymer such as a polyester film that is laminated with a barrier
layer material such as polyethylene and/or polyvinylidene chloride
(PVDC). In step 612, the circuit pattern is cured and a conductive
epoxy material is applied. In step 614 an integrated circuit chip
is aligned onto the base layer. In step 616, two (2) batteries are
aligned onto the base layer. In an alternate enclosed transceiver,
the batteries are stacked vertically in either a series or parallel
electrical connection. In step 618, the epoxy applied in step 612
is cured. In step 620, a stiffener material is applied. In step 622
epoxy is applied to the top surface of the battery and then the top
half of the base layer is folded over the bottom half so that the
top half forms the top cover. In step 624, the epoxy material
applied in step 622 is cured. Finally, in step 626, the package is
sealed to complete manufacturing of the package.
[0108] Various modifications may be made in and to the above
described embodiments without departing from the spirit and scope
of this invention. For example, various modifications and changes
may be made in the antenna configurations, battery arrangements
(such as battery stacking), device materials, device fabrication
steps, and the functional block diagrams without departing from the
scope of this invention. The various off-chip components such as
the antenna, battery, and capacitor are manufactured on-chip in
alternate and equivalent embodiments. As a second example, the
antenna in another alternate and equivalent embodiment is formed on
the outer surface or within the outer film. In such an arrangement,
coupling to the antenna is through the capacitance of the outer
film as a dielectric. When formed on the exterior, the material
comprising the antenna also provides hermeticity to the film for
protecting the enclosed transceiver. Accordingly, these and
equivalent structural modifications are within the scope of the
following appended claims.
[0109] As previously suggested, an enclosed transceiver used as an
RFID device has utility directed to a wide variety of applications
including, but not limited to, airline baggage (luggage, freight,
and mail); parcel post (Federal Express and United Parcel Service);
U.S. Mail; manufacturing; inventory; personnel security.
[0110] While the particular invention has been described with
reference to illustrative embodiments, this description is not
meant to be construed in a limiting sense. It is understood that
although the present invention has been described in a preferred
embodiment, various modifications of the illustrative embodiments,
as well as additional embodiments of the invention, will be
apparent to persons skilled in the art, upon reference to this
description without departing from the spirit of the invention, as
recited in the claims appended hereto. It is therefore contemplated
that the appended claims will cover any such modifications or
embodiments as fall within the true scope of the invention.
[0111] The words and phrases used in the claims are intended to be
broadly construed. A "sticker" refers generally to a label, tag,
marker, stamp, identifier, packing slip, invoice, package seal,
tape, band, clasp, medallion, emblem, shield, and escutcheon
regardless of printed or handwritten material thereon. Mechanical
coupling of a "sticker" so defined to an article, person, plant, or
animal is not restricted to adhesive but is intended to broadly
include all forms of fastening, tieing, and securing.
* * * * *