U.S. patent application number 14/171378 was filed with the patent office on 2015-07-02 for gas sensor having micro-package structure and method for making the same.
This patent application is currently assigned to LINGSEN PRECISION INDUSTRIES, LTD.. The applicant listed for this patent is LINGSEN PRECISION INDUSTRIES, LTD.. Invention is credited to Chien-Ko LIAO, Tzu-Chih LIN.
Application Number | 20150185148 14/171378 |
Document ID | / |
Family ID | 53397089 |
Filed Date | 2015-07-02 |
United States Patent
Application |
20150185148 |
Kind Code |
A1 |
LIN; Tzu-Chih ; et
al. |
July 2, 2015 |
GAS SENSOR HAVING MICRO-PACKAGE STRUCTURE AND METHOD FOR MAKING THE
SAME
Abstract
A gas sensor having a micro-package structure includes a
light-emitting unit, a light-receiving unit, and a
signal-processing unit all deposited on a substrate, and a package
body fixed to the substrate and having a chamber and a through
hole. The chamber accommodates all the units and the through hole
is over the substrate. Gas enters the chamber through the through
hole. The light-emitting unit emits an optical signal that passes
through the gas and then is received by the light-receiving unit.
Then a signal-processing unit electrically connected to the
light-receiving unit performs spectral analysis. Thereby, the gas
sensor is advantageous for requiring low packaging costs and being
compact.
Inventors: |
LIN; Tzu-Chih; (Taichung
City, TW) ; LIAO; Chien-Ko; (Taichung City,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LINGSEN PRECISION INDUSTRIES, LTD. |
Taichung City |
|
TW |
|
|
Assignee: |
LINGSEN PRECISION INDUSTRIES,
LTD.
Taichung City
TW
|
Family ID: |
53397089 |
Appl. No.: |
14/171378 |
Filed: |
February 3, 2014 |
Current U.S.
Class: |
250/343 ;
156/330; 156/60; 228/180.5; 29/831 |
Current CPC
Class: |
G01N 21/3504 20130101;
H01L 2924/00014 20130101; H01L 24/73 20130101; Y10T 29/49128
20150115; H01L 2224/45169 20130101; H01L 2224/73265 20130101; H01L
2924/16151 20130101; H01L 2224/73265 20130101; G01N 2021/3155
20130101; Y10T 156/10 20150115; G01N 33/0027 20130101; H01L
2224/32225 20130101; H01L 2224/48227 20130101; H01L 2924/00012
20130101; H01L 2924/207 20130101; H01L 2924/00014 20130101; H01L
2924/00012 20130101; H01L 2224/45015 20130101; H01L 2924/181
20130101; H01L 2224/45169 20130101; H01L 2224/32225 20130101; H01L
2224/48227 20130101; H01L 2924/00014 20130101; H01L 24/48 20130101;
H01L 24/32 20130101; H01L 2224/48091 20130101; H01L 2924/181
20130101; H01L 24/45 20130101 |
International
Class: |
G01N 21/61 20060101
G01N021/61; H01L 23/00 20060101 H01L023/00; C09J 5/00 20060101
C09J005/00; G01N 33/00 20060101 G01N033/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 27, 2013 |
TW |
102148858 |
Claims
1. A gas sensor having a micro-package structure, the gas sensor
comprising: a substrate, having a light-emitting area, a
light-receiving area, and a signal-processing area: a
light-emitting unit, being deposited in the light-emitting area and
providing an optical signal; a light-receiving unit, being
deposited in the light-receiving area and receiving the optical
signal of the light-emitting unit; a signal-processing unit, being
deposited in the signal-processing area and electrically connected
to the light-receiving unit; and a package body, being fixed to the
substrate and having a chamber and a through hole, wherein the
chamber accommodates the light-emitting unit, the light-receiving
unit, and the signal-processing unit, and the through hole is over
the substrate.
2. The gas sensor of claim 1, wherein the signal-processing unit is
a die.
3. The gas sensor of claim 2, wherein a protective layer is formed
on a surface of the signal-processing unit.
4. The gas sensor of claim 1, wherein the package body includes an
upper lid and a lateral wall circling the upper lid and extending
downward from the upper lid, and the upper lid is provided with the
through hole, and defines the chamber jointly with the lateral
wall.
5. The gas sensor of claim 1, wherein the optical signal of the
light-emitting unit is a visible light or an infrared ray, with a
wavelength between 380 nm and 10000 nm.
6. The gas sensor of claim 1, wherein the light-receiving unit is
an infrared-ray sensor.
7. A method for making the gas sensor having the micro-package
structure of claim 1, the method comprising the following steps:
providing the substrate and defining the light-emitting area, the
light-receiving area, and the signal-processing area; providing the
light-emitting unit, the light-receiving unit, and the
signal-processing unit in the light-emitting area, the
light-receiving area, and the signal-processing area, respectively;
providing an electrically-connecting means to the substrate and the
signal-processing unit; and providing a fixedly-connecting means
between the package body and the substrate.
8. The method of claim 7, wherein the electrically-connecting means
is a wire bonding process.
9. The method of claim 7, wherein the fixedly-connecting means is
gluing.
10. method of claim 9, wherein an adhesive used for the
fixedly-connecting means is epoxy resin.
11. The method of claim 7, further comprising a step of providing a
protective layer on a surface of the signal-processing unit.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] The present invention relates to sensors, and more
particularly to a gas sensor having a micro-package structure and a
method for making the gas sensor.
[0003] 2. Description of Related Art
[0004] A gas sensor works by using applicable electric signals to
convert a certain gas in the air into figures for convenient
monitoring and calculation. In the air, most gases are colorless
and odorless, and thus undetectable by human olfaction or other
human sensory functions. However, some of the gases may be
dangerous when presenting in the air we breathe. Carbon monoxide,
for example, when inhaled excessively by people, the people can be
poisoned to faint or even die. This can be prevented and human
safety can be ensured by using a gas sensor and taking appropriate
ventilating measures. In another instance where the levels of
carbon dioxide and oxygen in the air are to be controlled for
people's good life quality, a gas sensor may be attached to an
air-conditioning system so that when the level of carbon dioxide is
higher than desired, the air-conditioning system can activate its
air purifier to improve the air quality. It is thus evidenced that
gas sensors are important to improvement in comfort and safety of
human life.
[0005] FIG. 1 and FIG. 2 depict a conventional solid-electrolyte
gas-sensing module 1, which comprises a substrate 2, a gas-sensing
element 3 deposited on the substrate 2, and a metal cover 4 fixed
to the substrate 2 and covering the gas-sensing element 3. The
gas-sensing element 3 is composed of a solid electrolyte 5 of
cation (Na.sup.+) and a printed heater (RuO.sub.2)8 provided
between a cathode (sensing electrode) 6 and an anode (counter
electrode) 7. The cathode 6 is made from lithium carbonate and
gold, and is connected to a first leading pin S1. The anode 7 is
made of gold, and is connected to a second leading pin S2. The
printed heater 8 is connected to a third leading pin (not shown)
and a fourth leading pin (not shown). The gas-sensing element 3
further uses platinum wires to connect connecting pins 9 made of
nickel for signal transmission. Such a gas-sensing module 1 has
been rapidly developed for having advantages of high conductivity,
high sensitivity, and high versatility as the gas-sensing element 3
can be modified by varying the ions generated in the material
through absorption, the moving ions in the electrolyte, and the
immobilized ions in the material. However, the gas-sensing element
3 is structurally complex and requires high manufacturing costs, so
the price of the entire gas-detecting module 1 is consequently
expansive. In addition, since a gas-sensing structure of this type
is typically made as a voluminous modularized device, its use is
subject to spatial abundance.
[0006] To sum up, the conventional gas-detecting module is
imperfect and needs to be improved.
BRIEF SUMMARY OF THE INVENTION
[0007] The primary objective of the present invention is to provide
a gas sensor having a micro-package structure and a method for
making the same. The gas sensor requires less packaging costs, and
is compact, thereby being more practical.
[0008] For achieving the above-mentioned objective, the gas sensor
of the present invention comprises a substrate, a light-emitting
unit, a light-receiving unit, a signal-processing unit, and a
package body. The substrate has a light-emitting area, a
light-receiving area, and a signal-processing area. The
light-emitting unit is deposited in the light-emitting area and
provides an optical signal. The light-receiving unit is deposited
in the light-receiving area and receives the optical signal of the
light-emitting unit. The signal-processing unit is deposited in the
signal-processing area and electrically connected to the
light-receiving unit. The package body is fixed to the substrate
and has a chamber and a through hole. The chamber accommodates the
light-emitting unit, the light-receiving unit, and the
signal-processing unit, and the through hole is over the
substrate.
[0009] Therein, the signal-processing unit is a die.
[0010] Therein, a protective layer is formed on a surface of the
signal-processing unit.
[0011] Therein, the package body includes an upper lid and a
lateral wall circling the upper lid and extending downward from the
upper lid, and the upper lid is provided with the through hole, and
defines the chamber jointly with the lateral wall.
[0012] Therein, the optical signal of the light-emitting unit is a
visible light or an infrared ray, with a wavelength between 380 nm
and 10000 nm.
[0013] Therein, the light-receiving unit is an infrared-ray sensor
(IR Sensor).
[0014] Therein, the gas sensor further comprises a step of
providing the protective layer on a surface of the
signal-processing unit.
[0015] For achieving the above-mentioned objective, the present
invention further provides a method for making the gas sensor,
which comprises the following steps: providing the substrate and
defining the light-emitting area, the light-receiving area and the
signal-processing area; providing the light-emitting unit, the
light-receiving unit and the signal-processing unit to the
light-emitting area, the light-receiving area and the
signal-processing area, respectively; providing an
electrically-connecting means to the substrate and the
signal-processing unit; and providing a fixedly-connecting means
between the package body and the substrate.
[0016] Therein, the electrically-connecting means is a wire bonding
process.
[0017] Therein, the fixedly-connecting means is gluing.
[0018] Thereby, the disclosed gas sensor is small and compact, and
uses simplified manufacturing process so as to reduce the packaging
costs, thereby being more practical as compared to the prior
art.
[0019] For further illustrating the means and functions by which
the present invention achieves the certain objectives, the
following description, in conjunction with the accompanying
drawings and preferred embodiments, is set forth as below to
illustrate the implement, structure, features and effects of the
subject matter of the present invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0020] The invention as well as a preferred mode of use, further
objectives and advantages thereof will be best understood by
reference to the following detailed description of illustrative
embodiments when read in conjunction with the accompanying
drawings, wherein:
[0021] FIG. 1 is a perspective view of a conventional gas-detecting
module;
[0022] FIG. 2 is a cross-sectional view of the conventional
gas-detecting module, showing the interior of its gas-sensing
element;
[0023] FIG. 3 is a cross-sectional view of a gas sensor according
to one preferred embodiment of the present invention, showing the
light-emitting unit delivering an optical signal to the
light-receiving unit;
[0024] FIG. 4 is a top view of the gas sensor according to the
preferred embodiment of the present invention, showing the layout
of the units on the substrate; and
[0025] FIG. 5A through FIG. 5C illustrate the method for making the
gas sensor according to another preferred embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0026] The following preferred embodiments when read with the
accompanying drawings are made to clearly exhibit the
above-mentioned and other technical contents, features and effects
of the present invention.
[0027] Referring to FIG. 3 through FIG. 4, in a preferred
embodiment of the present invention, a gas sensor 10 comprises a
substrate 20, a light-emitting unit 30, a light-receiving unit 40,
a signal-processing unit 50 and a package body 60.
[0028] The substrate 20 has a light-emitting area 21, a
light-receiving area 23, and a signal-processing area 25.
[0029] The light-emitting unit 30 is deposited in the
light-emitting area 21 and provides an optical signal 31. The
optical signal 31 of the light-emitting unit 30 may be a visible
light or an infrared ray, with a wavelength between 380 nm and
10000 nm. In the present embodiment, the optical signal 31 is an
infrared ray
[0030] The light-receiving unit 40 is deposited in the
light-receiving area 23 and receives the optical signal 31 from the
light-emitting unit 30. The light-receiving unit 40 in the present
embodiment is an infrared-ray sensor (IR Sensor).
[0031] The signal-processing unit 50 is deposited in the
signal-processing area 25 and is electrically connected to the
light-receiving unit 40. In the present embodiment, the
signal-processing unit 50 is realized by a die, for replacing the
conventional gas-sensing element 3 and being much less voluminous.
For protecting the signal-processing unit 50 in the form of the die
from dust and moisture, a taping machine (not shown) is used to
form a protective layer 51 over the signal-processing unit 50, so
as to protect it without excessively adding its volume.
[0032] The package body 60 is fixed to the substrate 20, and
includes an upper lid 61 and a lateral wall 63 circling the upper
lid 61 and extending downward from the upper lid 61. The upper lid
61 has a through hole 65, and defines jointly with the lateral wall
63 a chamber 67. The chamber 67 accommodates the light-emitting
unit 30, the light-receiving unit 40, and the signal-processing
unit 50. The through hole 65 is formed above the substrate 20. In
the present embodiment, the through hole 65 is preferably formed
between the light-receiving unit 40 and the signal-processing unit
50.
[0033] FIG. 5A through FIG. 5C illustrate a method for making the
gas sensor 10 according to another preferred embodiment the present
invention. The method comprises the following steps:
[0034] Step A: providing the substrate 20 and defining the
light-emitting area 21, the light-receiving area 23, and the
signal-processing area 25, and electrically connecting the
light-emitting unit 30, the light-receiving unit 40 and the
signal-processing unit 50 to the light-emitting area 21, the
light-receiving area 23 and the signal-processing area 25,
respectively;
[0035] Step B: providing an electrically-connecting means to the
substrate 20 and the signal-processing unit 50, wherein the
electrically-connecting means is using a wire bonding process to
make at least one wire bond 70 connected between the substrate 20
and the signal-processing unit 50; and
[0036] Step C: providing a fixedly-connecting means between the
package body 60 and the substrate 20, wherein the
fixedly-connecting means is gluing and in the present embodiment an
adhesive use for the gluing is epoxy resin.
[0037] When the disclosed gas sensor 10 is used for gas detection,
the gas to be detected flows into the chamber 67 of the package
body 60 through the through hole 65 formed on the upper lid 61, and
the infrared ray emitted by the light-emitting unit 30 passes
through the gas to be detected and casts on the light-receiving
unit 40. At the same time, the infrared ray has its wavelength
affected by the gas to be detected, so the light-receiving unit 40
receiving the infrared ray works to identify the spectrum of the
changed wavelength, and then passes the data to the
signal-processing unit 50 for processing and analysis. At last, the
data are converted into signals and output to a reading device (not
shown) or a display device (not shown), so that the spectrum of the
gas to be detected can be read out our displayed for a user to
determine what the gas is.
[0038] In conclusion, the disclosed gas sensor 10 is small and
compact, and uses simplified manufacturing process so as to reduce
the packaging costs, thereby being more practical as compared to
the prior art.
[0039] The present invention has been described with reference to
the preferred embodiments and it is understood that the embodiments
are not intended to limit the scope of the present invention.
Moreover, as the contents disclosed herein should be readily
understood and can be implemented by a person skilled in the art,
all equivalent changes or modifications which do not depart from
the concept of the present invention should be encompassed by the
appended claims.
* * * * *