U.S. patent application number 16/118113 was filed with the patent office on 2020-03-05 for compact transceiver on a multi-level integrated circuit.
The applicant listed for this patent is Ferric Inc.. Invention is credited to Michael Lekas, Noah Sturcken.
Application Number | 20200075233 16/118113 |
Document ID | / |
Family ID | 69641548 |
Filed Date | 2020-03-05 |
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United States Patent
Application |
20200075233 |
Kind Code |
A1 |
Lekas; Michael ; et
al. |
March 5, 2020 |
Compact Transceiver on a Multi-Level Integrated Circuit
Abstract
Power and/or data are transmitted through variable magnetic
fields between a first transceiver coil on a transceiver apparatus
and a second transceiver coil in an inductor integrated into a
multilevel wiring structure on a semiconductor integrated circuit
chip. The first transceiver apparatus generates magnetic fields and
can transmit data by varying a characteristic of the magnetic
fields. The second transceiver coil receives the power from and/or
detects data in the magnetic fields from the first transceiver
apparatus. The inductor can include a ferromagnetic core that
concentrates magnetic flux to improve data or power transmission
efficiency to miniaturize the second transceiver coil while
maintaining adequate inductive coupling between the coils. The
second transceiver coil can transmit data by varying the impedance
of the inductor and/or the integrated circuit. The semiconductor
integrated circuit chip can be coupled to an object and the second
transceiver coil can transmit data relating to the object.
Inventors: |
Lekas; Michael; (New York,
NY) ; Sturcken; Noah; (New York, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ferric Inc. |
New York |
NY |
US |
|
|
Family ID: |
69641548 |
Appl. No.: |
16/118113 |
Filed: |
August 30, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 23/645 20130101;
H01F 38/14 20130101; H04B 5/0037 20130101; H01F 27/40 20130101;
H04B 5/0031 20130101; H01F 2038/143 20130101; H01F 27/24 20130101;
H01F 27/2804 20130101; H02J 50/005 20200101; H01F 27/365 20130101;
H01L 2223/6627 20130101; H02J 50/12 20160201 |
International
Class: |
H01F 38/14 20060101
H01F038/14; H01L 23/64 20060101 H01L023/64; H02J 50/12 20060101
H02J050/12; H01F 27/24 20060101 H01F027/24; H04B 5/00 20060101
H04B005/00 |
Claims
1. A system for transmitting power or data through variable
magnetic fields, comprising: a first transceiver apparatus
comprising a first transceiver coil that generates first variable
magnetic fields; a semiconductor integrated circuit comprising a
multilevel wiring network fabricated on a semiconductor die; and an
inductor integrated into the multilevel wiring network, wherein the
inductor comprises: a magnetic core; and a second transceiver coil
that is wound in a generally spiral manner on the outside of the
magnetic core, the second transceiver coil including at least one
level from the multilevel wiring network, wherein the second
transceiver coil is electrically coupled to active circuit elements
on the semiconductor die, and the first and second transceiver
coils are inductively coupled to each other.
2. The system of claim 1, wherein the magnetic core includes a
ferromagnetic material that concentrates a magnetic flux at the
second transceiver coil to improve the inductive coupling between
the first and second transceiver coils.
3. The system of claim 2, wherein the ferromagnetic material has a
relative permeability of 50 or greater.
4. The system of claim 2, wherein the magnetic core includes an
alternating sequence of ferromagnetic layers and insulating layers,
each insulating layer disposed between neighboring ferromagnetic
layers, wherein the insulating layers suppress eddy currents in the
presence of alternative magnetic fields up to 3 GHz in
frequency.
5. The system of claim 2, wherein the ferromagnetic material is
between 100 nm and 10,000 nm in thickness.
6. The system of claim 1, wherein the active circuit elements are
configured to modulate a combined impedance of the second
transceiver coil and the semiconductor integrated circuit to
transmit data to the first transceiver coil.
7. The system of claim 1, wherein the second transceiver coil
comprises a first conductive interconnect layer on a first level of
the multilevel wiring network, a second conductive interconnect
layer on a second level of the multilevel wiring network, and
vertical interconnect accesses (VIAs) that electrically couple the
first and second conductive interconnect layers through openings
defined in an electrically-insulating dielectric material that
otherwise electrically isolates the first and second conductive
interconnect layers from each other and from the magnetic core,
whereby the second transceiver coil has a solenoid
configuration.
8. The system of claim 7, wherein the magnetic core includes a
ferromagnetic material that increases an inductance of the
inductor, the magnetic core disposed between the first and second
conductive interconnect layers.
9. The system of claim 8, wherein the ferromagnetic material is
characterized by low magnetic coercivity along an axis, the second
transceiver coil extending along the axis.
10. The system of claim 1, wherein the semiconductor die, including
the semiconductor integrated circuit and the inductor, has a length
of less than 1 mm, a width of less than 1 mm, and a height of less
than 1 mm.
11. The system of claim 10, wherein the length is less than 0.4 mm,
the width is less than 0.4 mm, and the height is less than 0.2
mm.
12. The system of claim 1, wherein a diameter of the first
transceiver coil is larger than the largest dimension of the
semiconductor die so that the semiconductor die can be disposed
within the first transceiver coil.
13. The system of claim 1, wherein the first and second transceiver
coils are disposed so that an angle between a first magnetic flux
axis and a second magnetic flux is 0 degrees to 60 degrees, wherein
a first magnetic flux passes through an interior of the first
transceiver coil along the first magnetic flux axis and the second
magnetic flux passes through an interior of the second transceiver
coil along the second magnetic flux axis.
14. The system of claim 1, wherein the multilevel wiring network is
wire routed in a star pattern or in a spine pattern to reduce
parasitic magnetic coupling between (a) the first and second
transceiver coils and (b) the multilevel wiring network that does
not include the second transceiver coil.
15. The system of claim 1, further comprising an additional second
transceiver coil, wherein a second magnetic flux passes through an
interior of each second transceiver coil along a respective second
magnetic flux axis, the second magnetic flux axes orthogonal to
each other.
16. The system of claim 1, wherein the semiconductor integrated
circuit includes logic to modulate an impedance of the inductor to
transmit data to the first transceiver apparatus.
17. The system of claim 16, wherein the semiconductor die is
mechanically coupled to an object and the logic is configured to
transmit data relating to the object.
18. A method for transmitting power or data through magnetic
fields, comprising: passing a first variable electrical current
through a first transceiver coil in a first transceiver apparatus;
generating a variable magnetic flux that passes through an interior
of the first transceiver coil, the variable magnetic flux extending
along a first flux axis to a semiconductor integrated circuit chip,
the semiconductor integrated circuit chip including a second
transceiver coil disposed about an outside of a magnetic core;
generating a second variable current in the second transceiver
coil, the second variable current based on the variable magnetic
flux; and modulating an impedance of the second transceiver coil to
transmit data to the first transceiver apparatus.
19. The method of claim 18, further comprising passing the second
variable current through an integrated circuit on the semiconductor
integrated circuit chip, the integrated circuit comprising a
multilevel wiring structure that is electrically coupled to active
circuit elements.
20. The method of claim 19, wherein the integrated circuit is
configured with logic to modulate the impedance of the second
transceiver coil to transmit the data to the first transceiver
coil.
21. The method of claim 20, wherein the logic is configured to
transmit encrypted data to the first transceiver coil.
22. The method of claim 21, wherein the encrypted data includes a
unique identifier relating to an object, the object mechanically
and/or electrically coupled to the semiconductor integrated circuit
chip.
23. The method of claim 22, further comprising detecting the
modulated impedance with the first transceiver apparatus to receive
the encrypted data.
24. The method of claim 22, further comprising, with the first
transceiver apparatus: decrypting the encrypted data to receive the
unique identifier; querying a database in communication with the
first transceiver apparatus to determine if the unique identifier
exists in the database; determining that the object is authentic
when the unique identifier exists in the database; and determining
that the object is fraudulent when the unique identifier does not
exist in the database.
25. The method of claim 18, further comprising modulating an
impedance of the first transceiver coil to transmit data to the
second transceiver coil.
26. The method of claim 18, further comprising angularly
restricting an angle between a first magnetic flux axis and a
second magnetic flux axis to an angular range of 0 degrees to 60
degrees, wherein a first magnetic flux passes through an interior
of the first transceiver coil along the first magnetic flux axis
and the second magnetic flux passes through an interior of the
second transceiver coil along the second magnetic flux axis.
Description
TECHNICAL FIELD
[0001] This application relates generally to wireless transmission
of power and/or signals using inductive coupling.
BACKGROUND
[0002] Inductive coupling is commonly used for wireless power and
data transfer in modern electrical systems. Near-field magnetic
induction systems often employ a pair of electrical coils to induce
and sense changes in magnetic flux, which provides a wireless link
between the electrical coils to transfer signals and power. The
inductive coupling coefficient, k, at the frequency of signal/power
transmission is the key figure of merit for such wireless links, as
it represents the fraction of power or signal that is emitted from
one coil and received by another. A higher coupling coefficient
corresponds to higher efficiency for power transfer over the
wireless link, or higher signal-to-noise ratio for signals
transferred over the link. The coupling coefficient between a pair
of coils is dependent on the design of both coils as well as the
relative placement and orientation of each coil with respect to the
other.
[0003] For a given wireless inductive link there is a minimum
received signal or power level at which the link is functional. If
the signal or power level received is less than this level, the
receiver may not be able to discern between actual signal
information and noise that is present in the system, or the power
received may be too low for any dependent voltage conversion
functions to operate correctly.
[0004] It would be desirable to decrease the size of one of the
electrical coils, for example to attach or integrate the electrical
coil onto or into another object. However, there is no known method
to decrease the electrical coil's size without decreasing its
coupling coefficient.
SUMMARY
[0005] Example embodiments described herein have innovative
features, no single one of which is indispensable or solely
responsible for their desirable attributes. The following
description and drawings set forth certain illustrative
implementations of the disclosure in detail, which are indicative
of several exemplary ways in which the various principles of the
disclosure may be carried out. The illustrative examples, however,
are not exhaustive of the many possible embodiments of the
disclosure. Without limiting the scope of the claims, some of the
advantageous features will now be summarized. Other objects,
advantages and novel features of the disclosure will be set forth
in the following detailed description of the disclosure when
considered in conjunction with the drawings, which are intended to
illustrate, not limit, the invention.
[0006] An aspect of the invention is directed to a system for
transmitting power or data through variable magnetic fields. The
system comprises a first transceiver apparatus comprising a first
transceiver coil that generates first variable magnetic fields; a
semiconductor integrated circuit comprising a multilevel wiring
network fabricated on a semiconductor die; and an inductor
integrated into the multilevel wiring network. The inductor
comprises a magnetic core; and a second transceiver coil that is
wound in a generally spiral manner on the outside of the magnetic
core, the second transceiver coil including at least one level from
the multilevel wiring network. The conductive winding is
electrically coupled to active circuit elements on the
semiconductor die, and the first and second transceiver coils are
inductively coupled to each other.
[0007] In one or more embodiments, the magnetic core includes a
ferromagnetic material that concentrates a magnetic flux at the
second transceiver coil to improve the inductive coupling between
the first and second transceiver coils. In one or more embodiments,
the ferromagnetic material has a relative permeability of 50 or
greater. In one or more embodiments, the magnetic core includes an
alternating sequence of ferromagnetic layers and insulating layers,
each insulating layer disposed between neighboring ferromagnetic
layers, wherein the insulating layers suppress eddy currents in the
presence of alternative magnetic fields up to 3 GHz in frequency.
In one or more embodiments, the ferromagnetic material is between
100 nm and 10,000 nm in thickness.
[0008] In one or more embodiments, the active circuit elements are
configured to modulate a combined impedance of the second
transceiver coil and the semiconductor integrated circuit to
transmit data to the first transceiver coil. In one or more
embodiments, the second transceiver coil comprises a first
conductive interconnect layer on a first level of the multilevel
wiring network, a second conductive interconnect layer on a second
level of the multilevel wiring network, and vertical interconnect
accesses (VIAs) that electrically couple the first and second
conductive interconnect layers through openings defined in an
electrically-insulating dielectric material that otherwise
electrically isolates the first and second conductive interconnect
layers from each other and from the magnetic core, whereby the
second transceiver coil has a solenoid configuration. In one or
more embodiments, the magnetic core includes a ferromagnetic
material that increases an inductance of the inductor, the magnetic
core disposed between the first and second conductive interconnect
layers. In one or more embodiments, the ferromagnetic material is
characterized by low magnetic coercivity along an axis, the second
transceiver coil extending along the axis.
[0009] In one or more embodiments, semiconductor die, including the
semiconductor integrated circuit and the inductor, has a length of
less than 1 mm, a width of less than 1 mm, and a height of less
than 1 mm. In one or more embodiments, the length is less than 0.4
mm, the width is less than 0.4 mm, and the height is less than 0.2
mm. In one or more embodiments, a diameter of the first transceiver
coil is larger than the largest dimension of the semiconductor die
so that the semiconductor die can be disposed within the first
transceiver coil.
[0010] In one or more embodiments, the first and second transceiver
coils are disposed so that an angle between a first magnetic flux
axis and a second magnetic flux is 0 degrees to 60 degrees, wherein
a first magnetic flux passes through an interior of the first
transceiver coil along the first magnetic flux axis and the second
magnetic flux passes through an interior of the second transceiver
coil along the second magnetic flux axis. In one or more
embodiments, the multilevel wiring network is wire routed in a star
pattern or in a spine pattern to reduce parasitic magnetic coupling
between (a) the first and second transceiver coils and (b) the
multilevel wiring network that does not include the second
transceiver coil.
[0011] In one or more embodiments, the system further comprises an
additional second transceiver coil, wherein a second magnetic flux
passes through an interior of each second transceiver coil along a
respective second magnetic flux axis, the second magnetic flux axes
orthogonal to each other. In one or more embodiments, the
semiconductor integrated circuit includes logic to modulate an
impedance of the inductor to transmit data to the first transceiver
apparatus. In one or more embodiments, the semiconductor die is
mechanically coupled to an object and the logic is configured to
transmit data relating to the object.
[0012] Another aspect of the invention is directed to a method for
transmitting power or data through magnetic fields. The method
comprises passing a first variable electrical current through a
first transceiver coil in a first transceiver apparatus; generating
a variable magnetic flux that passes through an interior of the
first transceiver coil, the variable magnetic flux extending along
a first flux axis to a semiconductor integrated circuit chip, the
semiconductor integrated circuit chip including a second
transceiver coil disposed about an outside of a magnetic core;
generating a second variable current in the second transceiver
coil, the second variable current based on the variable magnetic
flux; and modulating an impedance of the second transceiver coil to
transmit data to the first transceiver apparatus.
[0013] In one or more embodiments, the method further comprises
passing the second variable current through an integrated circuit
on the semiconductor integrated circuit chip, the integrated
circuit comprising a multilevel wiring structure that is
electrically coupled to active circuit elements. In one or more
embodiments, the integrated circuit is configured with logic to
modulate the impedance of the second transceiver coil to transmit
the data to the first transceiver coil. In one or more embodiments,
the logic is configured to transmit encrypted data to the first
transceiver coil. In one or more embodiments, the encrypted data
includes a unique identifier relating to an object, the object
mechanically and/or electrically coupled to the semiconductor
integrated circuit chip.
[0014] In one or more embodiments, the method further comprises
detecting the modulated impedance with the first transceiver
apparatus to receive the encrypted data. In one or more
embodiments, the method further comprises, with the first
transceiver apparatus: decrypting the encrypted data to receive the
unique identifier; querying a database in communication with the
first transceiver apparatus to determine if the unique identifier
exists in the database; determining that the object is authentic
when the unique identifier exists in the database; and determining
that the object is fraudulent when the unique identifier does not
exist in the database.
[0015] In one or more embodiments, the method further comprises
modulating an impedance of the first transceiver coil to transmit
data to the second transceiver coil. In one or more embodiments,
the method further comprises angularly restricting an angle between
a first magnetic flux axis and a second magnetic flux axis to an
angular range of 0 degrees to 60 degrees, wherein a first magnetic
flux passes through an interior of the first transceiver coil along
the first magnetic flux axis and the second magnetic flux passes
through an interior of the second transceiver coil along the second
magnetic flux axis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] For a fuller understanding of the nature and advantages of
the present concepts, reference is made to the following detailed
description of preferred embodiments and in connection with the
accompanying drawings, in which:
[0017] FIG. 1 is a perspective view of a system for transferring
power or data through alternating magnetic fields according to one
or more embodiments;
[0018] FIG. 2 is a top view of an integrated circuit chip that
includes a second transceiver coil that is electrically coupled to
an integrated circuit;
[0019] FIG. 3 is a cross section of the integrated circuit chip
illustrated in FIG. 2;
[0020] FIG. 4 is a cross sectional view of a laminated magnetic
core according to one or more embodiments;
[0021] FIG. 5 illustrates a range of optimal orientations for
inductively coupling a first coil and a second coil according to
one or more embodiments;
[0022] FIG. 6 illustrates an apparatus that includes a plurality of
second coils according to one or more embodiments;
[0023] FIG. 7 is a simplified diagram of an integrated circuit chip
that includes an inductor that can function as a second transceiver
coil;
[0024] FIGS. 8A and 8B are a top view and a representative
cross-sectional view, respectively, of an air-core spiral inductor
fabricated on a semiconductor substrate according to the prior
art;
[0025] FIG. 9 is a flow chart of a method for transferring power or
data through magnetic fields;
[0026] FIG. 10 is a block diagram of the first transceiver
apparatus according to one or more embodiments; and
[0027] FIG. 11 is a schematic diagram of a portion of an integrated
circuit 1200 for the second transceiver coil according to one or
more embodiments.
DETAILED DESCRIPTION
[0028] A wireless communication and/or power link is formed by
inductively coupling first and second transceiver coils through a
variable magnetic field. The first transceiver coil is disposed on
or in a first transceiver apparatus. The second transceiver coil is
integrated into a multilevel wiring structure on a semiconductor
integrated circuit chip. The first transceiver coil generates the
variable magnetic field and it can transmit data, signals,
commands, and/or other information by varying or modulating a
characteristic (e.g., frequency and/or amplitude) of the variable
magnetic field. The second transceiver coil can transmit data,
signals, commands, and/or other information by varying or
modulating its impedance. The semiconductor integrated circuit,
including the second transceiver coil, can be coupled mechanically
and/or electrically to an object. The data, signals, commands,
and/or other information transmitted between the first and second
receiver coils can be related to the object. In one example, the
second transceiver coil transmits encrypted data that can be used
by the first transceiver apparatus to determine if the object is
authentic or fraudulent.
[0029] The second transceiver coil can correspond to the conductive
winding of an inductor. The inductor can include a ferromagnetic
core that concentrates the magnetic flux at the second transceiver
coil to improve the inductive coupling between the first and second
transceiver coils. The increased concentration of magnetic flux and
inductive flux coupling can allow the second transceiver coil to be
miniaturized without reducing the inductive coupling coefficient k
between the first and second coils.
[0030] FIG. 1 is a perspective view of a system 20 for transferring
power or data through alternating magnetic fields according to one
or more embodiments. The system 20 includes a first transceiver
coil 200 and a second transceiver coil 210.
[0031] The first transceiver coil 200 is disposed on or in a first
transceiver apparatus 201. In some embodiments, the first
transceiver coil 200 can be or can include an air-core inductor.
The first transceiver apparatus 201 can include a housing, a
display, a processor, memory, one or more network communication
ports and modems/radios (such as for wired and/or wireless (e.g.,
Wi-Fi, cellular, and/or Bluetooth) network communication), a user
interface (e.g., a keyboard, a mouse, a trackpad, and/or
button(s)), and/or other components. The first transceiver coil 200
is electrically coupled to an electrical circuit 220, which is
electrically coupled to a power supply 230. Though the power supply
230 is illustrated as a battery, the power supply 230 can be an AC
or a DC power supply. The circuit 220 and power supply 230 generate
a variable electrical current 240 (e.g., an alternating electrical
current, an oscillating electrical current, etc.) that flows
through the first transceiver coil 200. The variable electrical
current 240 flowing through the first transceiver coil 200 (e.g.,
through an air-core inductor that includes the first transceiver
coil 200) generates a corresponding variable magnetic field 250
that extends axially from the interior 205 of the first transceiver
coil 200 in a direction orthogonal to the direction of travel of
the variable electrical current 240 through the first coil 200
(e.g., based on the right-hand rule). In some embodiments, the
first transceiver apparatus 201 can modulate one or more
characteristics (e.g., amplitude and/or frequency) of the variable
electrical current 240 to transfer data, commands, signals, and/or
other information to the second transceiver coil 210.
[0032] The second transceiver coil 210 is disposed on or in an
object 211. The object 211 can be an item of merchandise, a
pharmaceutical (e.g., a pill, a container or bottle for pills or
liquid medication, etc.), a medical device (e.g., an implantable
medical device such as a neurostimulator, a pacemaker, an infusion
pump such as an insulin pump, a gastric simulator, a defibrillator,
or other implantable medical device), or a sensor (e.g., an
implantable sensor such as a glucose sensor, a blood flow or
pressure sensor, a heart rate sensor, a blood oxygen saturation
sensor, a biosensor, or an accelerometer).
[0033] The variable magnetic field 250, generated by the first
transceiver coil 200, passes through or adjacent to the second
transceiver coil 210 when the first and second transceiver coils
200, 210 are disposed proximal to each other (e.g., within about
one-half wavelength of the carrier frequency of the operating
current, which is generally between about 1 MHz and about 5 GHz,
including any range or frequency therebetween). The variable
magnetic field 250 generates a corresponding variable electrical
current in the second transceiver coil 210, which can be used to
power a device that is electrically coupled to the second
transceiver coil 210 and/or to transfer information (e.g., data,
commands, signals, etc.) back to the first transceiver apparatus
201. For example, the second transceiver coil 210 can be
electrically coupled to an electrical circuit that includes logic
to modulate the combined impedance of the second transceiver coil
210 and the electrical circuit. The modulated impedance can be
detected as data by the first transceiver coil 200 and associated
electronics in the first transceiver apparatus 201.
[0034] In some embodiments, the combined impedance of the second
transceiver coil 210 and the electrical circuit can be modulated to
transfer encrypted data to the first transceiver apparatus 201. The
encrypted data can be related to the object 201. For example, the
encrypted data can be used by the first transceiver coil 200 and
associated electronics to determine whether the object 201 is
authentic or fraudulent.
[0035] The first transceiver apparatus 201 can decrypt the received
encrypted data using a cryptographic method such as symmetric key
cryptography or asymmetric cryptography (e.g., public key
cryptography). After decrypting the data sent from the second
transceiver coil 210, the first transceiver apparatus 201 can
determine whether the object 201 is authentic based, at least in
part, on the decrypted data. For example, the first transceiver
apparatus 201 can query a database, which can be stored internally
or in network communication with the first transceiver apparatus
201, to determine if the database includes data that corresponds to
or is the same as the decrypted data, which can indicate that the
decrypted data--and thus the object 201--is authentic or
fraudulent. The decrypted data can be unique to the object 201
(e.g., its serial number or other unique identifier) or it can be
unique to the class of objects 201 (e.g., data that is unique to a
type and/or dose of a pharmaceutical pill).
[0036] In other embodiments, the combined impedance of the second
transceiver coil 210 and the integrated circuit can be modulated to
transfer data collected by an implanted medical device (e.g., a
sensor), data relating to the implanted medical device (e.g., the
charge level of its battery, its serial number, its software and/or
hardware revision number, etc.), and/or performance data of the
implanted medical device (e.g., the dates and times of past uses of
the implanted medical device, such as the dates and times of past
insulin injections, the volume of each injection). Some or all of
this data can be encrypted, for example to protect patient
privacy.
[0037] In some embodiments, the first transceiver coil 200 can have
a diameter 205 that is large enough to allow the integrated circuit
chip 30 (as described below) that includes the second transceiver
coil 210 to be placed or disposed in the interior 205 (e.g.,
center) of the first transceiver coil 200. For example, the
diameter 205 can be larger than the largest dimension of the
integrated circuit chip 30.
[0038] FIG. 2 is a top view of an integrated circuit chip 30 that
includes a second transceiver coil 310 that is electrically coupled
to an integrated circuit. The second transceiver coil 310 can be
the same as or different than the second transceiver coil 210. The
second transceiver coil 310 includes a planar magnetic core 320 and
a conductive winding 330 that turns around in a generally spiral
manner (e.g., like a solenoid) on the outside of the planar
magnetic core 320. The conductive winding 330 is piecewise
constructed of conductive segments 332 disposed on a first level of
a multilevel wiring structure of the integrated circuit, conductive
segments 334 disposed on a second level of a multilevel wiring
structure, and conductive interconnects (not illustrated) (e.g.,
vertical interconnect accesses or VIAs) that electrically connect
conductive segments on the first and second levels of the
multilevel wiring structure. The integrated circuit chip 30 can
include logic (e.g., logic gates such as in an application-specific
integrated circuit or ASIC) or a processor, which can provide the
logic for modulating the combined impedance of the second
transceiver coil 310 and the integrated circuit to send data to the
first transceiver coil 200. The integrated circuit chip 30 can
include one or more additional electrical components, in addition
to the second transceiver coil 310, such as one or more capacitors
(e.g., trench capacitors, MIM capacitors, etc.), one or more
resistors, one or more transformers, one or more diodes, and/or one
or more inductors. In addition, the integrated circuit chip 30 can
include an interface to electrically couple a portion of the
integrated circuit to an object (e.g., object 211) such as an
implanted medical device or other electrical device, for example to
receive information (e.g., data) from the implanted medical device
and to transfer at least a portion of the information to the first
transceiver apparatus 201. In another example, the interface allows
the second transceiver coil 310 to power the object (e.g., object
211) while the first transceiver coil generates a variable magnetic
field.
[0039] In some embodiments, the integrated circuit chip 30 can have
dimensions of less than or equal to 1 mm (length).times.1 mm
(width).times.1 mm (height), such as less than 0.5 mm
(length).times.0.5 mm (width).times.0.5 mm (height). In a specific
example, the integrated circuit chip 30 has dimensions of less than
or equal to 0.4 mm (length).times.0.4 mm (width).times.0.2 mm
(height).
[0040] FIG. 3 is a cross section through line 4-4 of integrated
circuit chip 30 according to one or more embodiments. Integrated
circuit chip 30 includes a multilevel wiring structure 400 disposed
on a substrate 410. Multilevel wiring structure 400 includes metal
wiring levels 420 and vertical conductive interconnects or VIAs 430
that electrically connect adjacent metal wiring levels 420. Metal
wiring levels 420 and VIAs 430 are constructed out of a conductive
material, such as copper and/or aluminum. Metal wiring levels 420
and VIAs 430 can include additional layers such as titanium,
titanium nitride, tantalum, tantalum nitride, and/or other layers.
It is noted that multilevel wiring structure 400 can include
additional or fewer metal wiring levels 420 and/or VIAs 430 than
the number illustrated in FIG. 3. The spaces in the multilevel
wiring structure 400 are filled with a dielectric insulating
material 440, such as silicon dioxide or silicon nitride.
[0041] A thin-film magnetic inductor 450 is integrated into at
least a portion of multilevel wiring structure 400. An example of
an inductor integrated into a multilevel wiring structure is
disclosed in U.S. Pat. No. 9,844,141, issued on Dec. 12, 2017,
entitled "Magnetic Core Inductor Integrated with Multilevel Wiring
Network," which is incorporated herein by reference.
[0042] The inductor 450 includes a single planar magnetic core 460,
which can be the same as or different than planar magnetic core
320. In some embodiments, the planar magnetic core 460 can have a
laminated configuration. The principal plane 470 of the planar
magnetic core 460 is substantially parallel with the planes (e.g.,
plane 425) defining each metal layer 420. The conductive winding or
coil of the inductor 450, which forms a general spiral (e.g., a
solenoid) on the outside of the planar magnetic core 460, is
piecewise constructed of wire segments 422A, 422B and of VIAs 432A,
432B. The wire segments 422A, 422B that form the winding pertain to
at least two of the metal wiring levels 420 (e.g., and the VIAs
432A, 432B that form the parts of the windings that are orthogonal
to the principal plane 470 are interconnecting the at least two
wiring metal wiring levels 420. The wire segments 422A, 422B can be
the same as or different than conductive segments 332, 334,
respectively. The conductive winding or coil of inductor 450 can be
the same as or different than the second transceiver coil 210
and/or 310. An insulator 465, such as silicon dioxide or silicon
nitride, is disposed around the core 460. In some embodiments, the
insulator can include a magnetic polymer material. An example of a
magnetic polymer material is disclosed in U.S. Patent Application
Publication No. 2017/0250133, titled "Systems and Methods for
Microelectronics Fabrication and Packaging Using a Magnetic
Polymer," published on Aug. 31, 2017, which is hereby incorporated
by reference.
[0043] The magnetic core 460 can be formed out of an anisotropic
material, such as a soft ferromagnetic material (e.g., such as iron
(Fe), cobalt (Co), and/or nickel (Ni)). in which the orientation of
anisotropy is permanently or semi-permanently fixed. For example,
the hard axis of magnetization of the anisotropic material in the
core 460 can be oriented parallel to the axis along which the
conductive winding or coil extends (into or out of the page in FIG.
3, for example out of the page as indicated by bullseye symbol
490). The easy axis of magnetization of the anisotropic material in
the core 460 is oriented orthogonally to the hard axis. Additional
details regarding anisotropy of magnetic cores are disclosed in
U.S. Pat. No. 9,991,040, titled "Apparatus and Methods for Magnetic
Core Inductors with Biased Permeability," issued on Jun. 5, 2018,
which is hereby incorporated by reference.
[0044] In some embodiments, inductor 450 has a small height 42,
such as less than about100 microns. The small height 42 provides a
low profile for inductor 450, allowing it to be integrated into
integrated circuit chip 30 in various locations and/or
configurations. A representative thickness of wire segments
422A/422B is about 1 .mu.m to about 20 .mu.m, about 5 .mu.m to
about 15 .mu.m, about 10 .mu.m, or any value or range between any
two of the foregoing thicknesses. A representative thickness of
magnetic core 460 is about 100 nm to about 10,000 nm, about 500 nm,
about 1,000 nm, about 2,500 nm, about 5,000 nm, about 7,500 nm, or
any value or range between any two of the foregoing thicknesses.
Therefore, a representative thickness of VIAs 432A/432B is slightly
larger than about 2 .mu.m to about 40 .mu.m, such as about 10 .mu.m
to about 30 .mu.m, about 15 .mu.m to about 18 .mu.m, about 20
.mu.m, or any value or range of the sum of the thickness of wire
segments 422A/422B and core 460. The VIAs 432A/432B can also have a
thickness greater than 22 .mu.m up to and including about 50 .mu.m
(or more), such as about 25 .mu.m, about 30 .mu.m, about 35 .mu.m,
about 40 .mu.m, about 45 .mu.m or any value or range between any
two of the foregoing thicknesses. A representative thickness of
insulator layer 465 is about 1 nm to about 10,000 nm, including
about 2,500 nm, about 5,000 nm, about 7,500 nm, or any value or
range between any two of the foregoing thicknesses. As used herein,
"about" means plus or minus 10% of the relevant value.
[0045] The substrate 410 can include silicon, silicon dioxide,
silicon nitride, a layered silicon-insulator structure (e.g.,
silicon on insulator or SOI), silicon germanium, or a III-V
structure such as aluminum gallium arsenide. A plurality of active
circuit elements 480, such as CMOS devices, are fabricated on the
substrate 410. The active circuit elements 480 may be any kind,
such as planar or three-dimensional FinFET type. The active circuit
elements 480 and the multilevel wiring structure 400 form an
integrated circuit that includes logic to modulate the combined
impedance of the conductive winding or coil of inductor 450 (e.g.,
second transceiver coil 210 and/or 310) and the integrated circuit
to transmit information (e.g., data) to the first transceiver
apparatus 201. In some embodiments, the multilevel wiring structure
400 is wire routed in a pattern that reduces or minimizes parasitic
magnetic coupling between (a) the first and/or second transceiver
coils 200, 210/310 and (b) the integrated circuit formed on the
integrated circuit chip 30 (excluding the conductive winding of
inductor 450). For example, the multilevel wiring structure 400,
not including the conductive winding of inductor 450, can be wire
routed in a star pattern or a spine pattern.
[0046] One or more optional components, shown as representative
structures 490, 492, can be integrated into the multilevel wiring
structure 400. The representative structure 490 and/or 492 can
include one or more capacitors (e.g., trench capacitors, MIM
capacitors, etc.), resistors, transformers, diodes, and/or
inductors. Such components, including inductor 450, can be
electrically coupled in series, in parallel, or a combination
thereof, to one another. For example, the integrated circuit chip
30 can include one or more capacitors (e.g., variable capacitors)
that form a resonant impedance matching circuit when combined with
an inductor (e.g., inductor 450) and/or a transformer, which
provides impedance transformation at a particular frequency band.
Modulation of the capacitance value in the resonant impedance
matching circuit may be used to alter the combined impedance of the
inductor (e.g., inductor 450) and the integrated circuit to
transmit data from the second coil to the first coil, with the
inductor functioning as an antenna.
[0047] FIG. 4 is a cross sectional view of a laminated magnetic
core 560 according to one or more embodiments. The core 560 can be
the same as or different than planar magnetic core 460. For
example, core 560 can be incorporated into inductor 450. The
laminated configuration of core 560 includes at least one layer of
a magnetic material 510 and at least one non-magnetic layer 520.
The purpose of the non-magnetic layer 520 is to prevent electrical
current circulation (e.g., eddy currents) in the planar magnetic
core 560 perpendicularly to the principal plane 540, which is
parallel with the lamination layers 510, 520. In one embodiment,
the magnetic core 560 can include an alternating sequence of up to
about 100 layers each, or about 2 to 50 periods 550 of the layers.
FIG. 4 shows 3 periods 550 of the layers, where each period 550
includes a magnetic layer 510 and a non-magnetic layer 520. When
the core 560 is integrated into inductor 450 (e.g., as the second
transceiver coil 210) and oriented as illustrated in FIG. 1, the
magnetic flux, from magnetic field 250, passing through the core
560 is orthogonal to the axis along which the magnetic and
non-magnetic layers 510, 520 are laminated and parallel to the axis
along which the conductive winding or solenoid of the inductor 450
extends (e.g., into or out of the page in FIGS. 3 and 4 with
respect to cores 460, 560, respectively).
[0048] In an alternative embodiment, the core 560 can include
vertical laminations (e.g., laminations that are orthogonal to the
laminations illustrated in FIG. 4), for example as disclosed in
U.S. Patent Application Publication No. 2018/0182530, titled
"Integrated Magnetic Core Inductor with Vertical Laminations,"
published on Jun. 28, 2018, which is hereby incorporated by
reference.
[0049] The magnetic layer 510 can include one or more soft
ferromagnetic materials, such as Fe, Co, and/or Ni. In one example,
the magnetic layer 510 includes CZT, or
Co.sub.xZr.sub.yTa.sub.1-x-y, with x and y being about 0.915 and
about 0.04, respectively. The soft ferromagnetic material(s) can be
anisotropic having a hard axis of magnetization that passes into or
out of the page in FIG. 4, for example as discussed above with
respect to core 460.
[0050] In some embodiments, the magnetic layer 510 has a high
relative permeability. For example, the relative permeability of
the magnetic layer 510 can be at least about 50, such as at least
about 75, at least about 100, at least about 125, or at least about
150. When the core 560 is integrated into inductor 450 (e.g., as
the second transceiver coil 210), the high relative permeability of
the magnetic layer 510 (and of the core 560) in the second
transceiver coil (e.g., second transceiver coil 210) acts to
concentrate the magnetic flux of the first transceiver coil (e.g.,
first transceiver coil 200) by increasing its inductance, such that
the cross-sectional area of the second transceiver coil can be
decreased by a factor equal to the relative permeability while
maintaining the same or similar identical inductive coupling
coefficient k between the first and second coils. For example, the
cross-sectional area of the second transceiver coil (e.g., the
cross section illustrated in FIG. 1) can be decreased by a factor
of 100 when the magnetic layer 510 has a relative permeability of
100 because about 100.times. more magnetic flux enters the core 560
compared to an air-core inductor. This can allow the
cross-sectional area of the second transceiver coil to be less than
1 mm.sup.2. Therefore, a high-permeability ferromagnetic core
allows the second transceiver apparatus to be substantially
miniaturized while maintaining comparable efficiency and fidelity
in signal and data transmission between the coils.
[0051] The non-magnetic layer 520 can include a dielectric or
insulator, such as SiO.sub.2 or CoO (including a material or
compound having any ratio of cobalt to oxygen atoms), and/or a
metal such as Ta and/or its related oxides and/or nitrides (e.g.,
Ta.sub.2O.sub.5, TaN, etc.). In some embodiments, non-magnetic
layer 520 itself can be composed of more than one constituent
layer. For example, the component layers of non-magnetic layer 520
can include an insulator layer 521 and a metal layer 522. The
insulator layer 521 can include SiO.sub.2, SiN (including a
material or compound having any ratio of silicon to nitrogen
atoms), CoO (including a material or compound having any ratio of
cobalt to oxygen atoms), polymers such as polyimide, and/or a
magnetic polymer. The metal layer 522 can include Ta, W, Ti, and/or
any of these metals' respective oxides or nitrides (e.g.,
Ta.sub.2O.sub.5, TaN, W.sub.2O.sub.3, W.sub.2N, TiO.sub.2, and/or
TiN). The purpose of the insulating layer 521 can be to prevent or
suppress electrical current circulation in the planar magnetic core
perpendicularly to the principal plane 540, which can occur in the
presence of an alternating or variable magnetic field. Such
perpendicular currents are known in the art as eddy currents, and
they would lead to energy losses for the inductor. In some
embodiments, the insulating layer 521 can prevent or suppress eddy
currents in the presence of alternating or variable magnetic fields
up to about 3 GHz in frequency. The effectiveness of a given
insulating layer or lamination in blocking eddy currents can be
based on its thickness, its dielectric constant, its electrical
resistivity, and cross-sectional area of the magnetic core.
[0052] The metal layer 522 can ease fabrication by smoothing the
surface during deposition. The non-magnetic layer 520 can have
structures and properties beyond those of simply having constituent
layers. In some embodiments of the present invention the
non-magnetic layer 520 can have current rectifying properties. For
example, the non-magnetic layer 520 can include a semiconducting
layer and an interface metal layer, the interface layer disposed
between the semiconducting layer and the magnetic layer 510. The
semiconducting layer can be a p-type semiconductor having a work
function less than the work function of magnetic layer 510.
Alternatively, the semiconducting layer can be an n-type
semiconductor having a work function greater than magnetic layer
510. The interface metal layer can have a work function less than
that of the p-type semiconducting material, or greater than that of
the n-type semiconducting material. In some embodiments, the
non-magnetic layer 520 includes semiconducting materials that form
a p-n junction (or n-p junction). In some embodiments, the
non-magnetic layer 520 forms a Schottky diode.
[0053] The sequential deposition of the various layers of the
laminated structure of core 560 can include some techniques known
in the semiconductor processing arts, for instance, masking,
sputtering, electroplating. The fabrication of one or more
components or layers of laminated magnetic core 560 may be done in
the presence of an applied magnetic field to magnetically orient
the deposited magnetic layers 510, such as to orient the easy or
hard axes of magnetization. For example, the hard axis of
magnetization can be oriented such that it is parallel to the axis
along which the conductive winding or coil of the inductor extends.
Thus, the core 560 can have low magnetic coercivity along the axis
along which the conductive winding or coil of the inductor
extends.
[0054] The thickness of the non-magnetic layers 520 may be in the
range of about 5 nm to about 100 nm, about 20 nm to about 80 nm,
about 40 nm to about 60 nm, about 50 nm, or any thickness between
any two of the foregoing values. The thickness of the magnetic
layers 510 can be about 100 nm to about 10,000 nm, including about
500 nm, about 1,000 nm, about 2,500 nm, about 5,000 nm, about 7,500
nm, or any thickness or thickness range between any two of the
foregoing values.
[0055] Considering the nature of its materials and its structural
requirements, representative embodiments of the invention may use
differing general approaches for fabricating the planar laminated
magnetic cores. A general approach may be centered on sputtering
and/or electroplating.
[0056] An example of a magnetic core, including a core having a
laminate configuration, can be found in U.S. Pat. No. 9,844,141,
titled "Magnetic Core Inductor Integrated with Multilevel Wiring
Network," issued on Dec. 12, 2017, U.S. Pat. No. 9,647,053, titled
"Systems and Methods for Integrated Multi-Layer Magnetic Films,"
issued on May 9, 2017, which are incorporated herein by
reference.
[0057] FIG. 5 illustrates a range of optimal orientations for
inductively coupling a first coil 600 and a second coil 610
according to one or more embodiments. The first coil 600 can be the
same as or different than first coil 200. The second coil 610 can
be the same as or different than second coil(s) 210 and/or 310. A
first magnetic flux, generated by the first coil 600, passes
through the interior 605 of the first coil 600 along a first flux
axis 620. A second magnetic flux, generated by the second coil 610,
passes through a center of the second coil 610 along a second flux
axis 630.
[0058] To provide an adequate power transfer and/or signal level
between the first and second coils 600, 610 (e.g., to maximize
inductive coupling), the first and second flux axes 620, 630 are
preferably aligned within a predetermined maximum alignment angle
640. For example, while keeping the orientation of the first coil
600 constant, the second coil 610 can be rotated such that the
second flux axis 630 is oriented parallel to axis 650, parallel to
axis 652, or any orientation therebetween. Of course, the first
coil 600 (or both coils 600, 610) can be rotated such that the
first flux axis 620 achieves the same relative orientations within
the predetermined maximum alignment angle 640.
[0059] In an alternative embodiment, an apparatus can include
multiple second coils oriented in different directions to increase
the likelihood that the flux axis of one the second coils is
oriented within the predetermined maximum alignment angle 640 of
the second first flux axis 620. For example, FIG. 6 illustrates an
apparatus 70 that includes three second coils 710A-C. The second
flux axis 720A of second coil 710A is parallel to reference axis
730. The second flux axis 720B of second coil 710B is orthogonal to
reference axis 730. The second flux axis 720B of second coil 710B
is oriented at an angle between 0.degree. and 90.degree. with
respect to reference axis 730, such as about 30.degree. to about
60.degree. or about 45.degree.. In other embodiments, the apparatus
70 can have additional or fewer second coils, which can be oriented
at any angle with respect to each other and with respect to
reference axis 730. Each second coil 710A-C can be disposed on the
same integrated circuit chip (e.g., integrated circuit chip 30) or
on different integrated circuit chips. Alternatively, two or more
second coils 710-C can be disposed on one integrated circuit chip
while the other second coil is integrated on a different integrated
circuit chip.
[0060] FIG. 7 is a simplified diagram of an integrated circuit chip
80 that includes an inductor 850 that can function as a second
transceiver coil. Inductor 850 is the same as inductor 450, but
inductor 850 is formed out of conductive segments 822A, B disposed
on the first two levels of a multilevel wiring structure. The
remainder of the multilevel wiring structure is not illustrated in
FIG. 7 for clarity. As illustrated, the magnetic flux through and
around the inductor 850 flows out of the page as it passes through
the core 860 (as indicated by the bullseye symbol) and it flows
into the page as it passes around the inductor 850 coil (as
indicated by the X symbol). At least a portion of the magnetic flux
800 that flows below conductive segment 822A passes through the
substrate 410 parallel to the surface 412 of substrate 410. Since
the magnetic flux 800 is parallel to the surface 412 of substrate
410, a smaller amount of magnetic flux 800 passes through the
substrate 410 than in prior art configurations, for example as
illustrated in FIGS. 8A-B. The smaller amount of magnetic flux 800
passing through the substrate 410 reduces the parasitic interaction
between the substrate 410 and the inductor 850. For example, the
configuration illustrated in FIG. 7 has a higher Q factor (a
measure of lossiness of an inductor) compared to the prior art
configuration illustrated in FIGS. 8A-B without affecting the
inductive coupling coefficient k. A higher Q factor provides an
increased signal-to-noise ratio for the Inductive coupling wireless
link. In some embodiments, the configuration illustrated in FIG. 7
has up to an 8.times. increase in Q factor compared to the
configuration illustrated in FIGS. 8A-B.
[0061] FIGS. 8A and 8B are a top view and a representative
cross-sectional view, respectively, of an air-core spiral inductor
90 fabricated on a semiconductor substrate 910 according to the
prior art. As illustrated, the magnetic flux 900 passes deeper into
the substrate 910 than in the configuration illustrated in FIG. 7,
which increases the parasitic interaction between the substrate 910
and the inductor 90 compared to the configuration illustrated in
FIG. 7.
[0062] FIG. 9 is a flow chart 1000 of a method for transferring
power or data through magnetic fields. In step 1010, a first
variable electrical current is passed through a first transceiver
coil in a first transceiver apparatus. In step 1020, a variable
magnetic flux that passes through an interior of the first
transceiver coil is generated. The variable magnetic flux extends
along a first flux axis to a semiconductor integrated circuit chip,
the semiconductor integrated circuit chip includes a second
transceiver coil disposed about an outside of a magnetic core. In
step 1030, a second variable current in the second transceiver coil
is generated. The second variable current is based, at least in
part, on the variable magnetic flux. In step 1040, the combined
impedance of the second transceiver coil and integrated circuit is
modulated (e.g., backscattered) to transmit data to the first
transceiver apparatus.
[0063] In some embodiments, the method further includes passing the
second variable current through an integrated circuit on the
semiconductor integrated circuit chip. The integrated circuit
includes a multilevel wiring structure that is electrically coupled
to active circuit elements. The integrated circuit can provide
logic to modulate the combined impedance of the second transceiver
coil and integrated circuit which can correspond to data in
unencrypted or in encrypted form.
[0064] In step 1050, the modulated impedance is detected by the
first transceiver apparatus to receive the transmitted data (e.g.,
the backscattered signal) from the second transceiver coil. If the
transmitted data is encrypted, the first transceiver apparatus can
decrypt it using a predetermined decryption method. In one example,
the transmitted data is a unique identifier relating to an object
that is mechanically and/or electrically coupled to the
semiconductor integrated circuit chip. After the transmitted data
is decrypted, the first transceiver apparatus can query a database
in network communication with the first transceiver apparatus to
determine if the unique identifier exists in the database. The
object can be determined to be authentic when the unique identifier
exists in the database. However, the object can be determined to be
fraudulent when the unique identifier does not exist in the
database.
[0065] In some embodiments, the impedance of the first transceiver
coil can be modulated to transmit data and/or commands to the
second transceiver coil. In some embodiments, the angle between a
first magnetic flux axis and a second magnetic flux axis can be
angularly restricted to an angular range of 0 degrees to 60
degrees. A first magnetic flux passes through an interior of the
first transceiver coil along the first magnetic flux axis and the
second magnetic flux passes through an interior of the second
transceiver coil along the second magnetic flux axis.
[0066] FIG. 10 is a block diagram of the first transceiver
apparatus 1101 according to one or more embodiments. The first
transceiver apparatus 1101 includes an electric circuit 1120 that
includes a power amplifier 1110, a low-noise amplifier 1120, and a
duplexer 1130. Additional portions of the electric circuit 1120,
for example to modulate and demodulate the transmitted and received
signals, are not illustrated in FIG. 10. The transmitted signal is
amplified by the power amplifier 1110 before it is transmitted to
the first coil 1100 via the duplexer 1130. The received signal
passes from the first coil 1100 to the duplexer 1130 and then to
the low-noise amplifier 1120.
[0067] FIG. 11 is a schematic diagram of a portion of an integrated
circuit 1200 for the second transceiver coil according to one or
more embodiments. The integrated circuit 1200 includes an inductor
1210, a variable capacitor 1220, and additional transceiver
electronics 1230. The inductor 1210 and the variable capacitor 1220
are in parallel electrically with each other. The inductor 1210 and
variable capacitor 1220 form a resonant impedance matching circuit
that provides impedance transformation at a particular frequency
band. Modulation of the capacitance value of the variable capacitor
1220 in the resonant impedance matching circuit may be used to
alter the combined impedance of the inductor 1210 and the
integrated circuit 1200 to transmit data from the second coil to
the first coil, with the inductor 1210 functioning as an
antenna.
[0068] The invention should not be considered limited to the
particular embodiments described above, but rather should be
understood to cover all aspects of the invention as fairly set out
in the attached claims. Various modifications, equivalent
processes, as well as numerous structures to which the invention
may be applicable, will be apparent to those skilled in the art to
which the invention is directed upon review of this disclosure. The
claims are intended to cover such modifications and
equivalents.
* * * * *