U.S. patent application number 16/991062 was filed with the patent office on 2022-02-17 for foldable force sensing device.
The applicant listed for this patent is UNIVERSAL CEMENT CORPORATION. Invention is credited to Shao-Chuan Fang, Chih-Sheng Hou.
Application Number | 20220050568 16/991062 |
Document ID | / |
Family ID | 1000005048656 |
Filed Date | 2022-02-17 |
United States Patent
Application |
20220050568 |
Kind Code |
A1 |
Fang; Shao-Chuan ; et
al. |
February 17, 2022 |
Foldable Force Sensing Device
Abstract
A force sensing device includes a sensor array, a first
substrate, a second substrate and a plurality of electrodes. The
first substrate has a sensor region and a side region. The second
substrate has a sensor region and a side region. The sensor array
is formed above the sensor region of the first substrate. The
plurality of electrodes are formed on the sensor region and the
side region of the first substrate and below the sensor region and
the side region of the second substrate, and coupled to the sensor
array. The side region of the first substrate, the side region of
the second substrate and the plurality of electrodes on the side
region are foldable to a back side of the sensor array.
Inventors: |
Fang; Shao-Chuan; (Taitung
County, TW) ; Hou; Chih-Sheng; (Taipei City,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UNIVERSAL CEMENT CORPORATION |
Taipei |
|
TW |
|
|
Family ID: |
1000005048656 |
Appl. No.: |
16/991062 |
Filed: |
August 12, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G01L 1/16 20130101; G06F
3/04166 20190501; G01L 1/18 20130101; G06F 3/0448 20190501; G06F
3/04144 20190501; G06F 1/1652 20130101 |
International
Class: |
G06F 3/041 20060101
G06F003/041; G01L 1/18 20060101 G01L001/18; G06F 1/16 20060101
G06F001/16; G01L 1/16 20060101 G01L001/16 |
Claims
1. A force sensing device comprising: a first substrate having a
sensor region, a side region, and a plurality of openings; a sensor
array formed above the sensor region of the first substrate; a
plurality of first electrodes formed on the sensor region and the
side region of the first substrate, and coupled to the sensor array
through gaps between the plurality of openings of the first
substrate; a second substrate having a sensor region and a side
region, and having a slit formed above the plurality of openings of
the first substrate and the gaps between the plurality of openings
of the first substrate, the sensor region of the second substrate
being above the sensor array; and a controller coupled to the first
electrodes; wherein the side region of the first substrate and the
plurality of first electrodes on the side region are foldable to a
back side of the sensor array.
2. The force sensing device of claim 1, further comprising: a
plurality of first insulation layers formed between the first
electrodes and the second substrate, across the slit of the second
substrate, and between the plurality of openings of the first
substrate.
3. The force sensing device of claim 1, wherein the force sensing
device is foldable along the plurality of openings of the first
substrate and the slit of the second substrate.
4. The force sensing device of claim 1, wherein: the second
substrate further has a plurality of openings; the first substrate
further has a slit formed below the plurality of openings of the
second substrate and gaps between the plurality of openings of the
second substrate; and the force sensing device further comprises: a
plurality of second electrodes formed on the sensor region and the
side region of the second substrate, and coupled to the sensor
array and the controller through the gaps between the plurality of
openings of the second substrate; and a plurality of second
insulation layers formed between the second electrodes and the
first substrate across the slit of the first substrate, and between
the plurality of openings of the second substrate.
5. The force sensing device of claim 4, wherein the force sensing
device is foldable along the plurality of openings of the second
substrate and the slit of the first substrate.
6. The force sensing device of claim 4, wherein the plurality of
first electrodes on the sensor region of the first substrate are
substantially perpendicular to the plurality of second electrodes
on the sensor region of the second substrate.
7. The force sensing device of claim 1, wherein the sensor array is
made of a piezoelectric material.
8. The force sensing device of claim 1, wherein the sensor array is
made of a piezoresistive material.
9. The force sensing device of claim 1, wherein the sensor array is
made of a piezo-capacitive material.
10. The force sensing device of claim 1, wherein the sensor array
comprises a plurality of pixels each comprising a force sensitive
material formed between a corresponding first electrode and a
corresponding second electrode.
11. The force sensing device of claim 10, wherein the plurality of
pixels are arranged into a matrix at fixed vertical intervals and
at fixed horizontal intervals.
12. The force sensing device of claim 1, wherein each of the pixels
comprises adhesion configured to adhere between the first substrate
and the second substrate.
13. A tiled device, comprising: a plurality of force sensing
devices tiled with each other, each force sensing device of the
plurality of force sensing devices comprising: a sensor array, the
sensor array comprising a matrix of pixels arranged at fixed
vertical intervals and at fixed horizontal intervals; a first
substrate having a plurality of openings; a plurality of first
electrodes arranged at a back side of the sensor array, formed on
the first substrate and coupled to the sensor array through gaps
between the plurality of openings of the first substrate; and a
second substrate having a slit formed above the plurality of
openings of the first substrate and the gaps between the plurality
of openings of the first substrate; and a controller arranged at
the back side of the sensor arrays of the each force sensing
device, and coupled to the plurality of first electrodes of the
each force sensing devices; wherein adjacent pixels between
vertically adjacent force sensing array devices of the plurality of
force sensing devices are arranged at the fixed vertical intervals;
and adjacent pixels between horizontally adjacent force sensing
array devices of the plurality of force sensing devices are
arranged at the fixed horizontal intervals.
14. (canceled)
15. The tiled device of claim 13, wherein the plurality of first
electrodes of the each force sensing devices are foldable to the
back side of the sensor array of the each force sensing device.
16. The tiled device of claim 13, wherein the each force sensing
device further comprises: a plurality of first insulation layers
formed between the first electrodes and the second substrate,
across the slit of the second substrate, and between the plurality
of openings of the first substrate.
17. The tiled device of claim 13, wherein the each force sensing
devices is foldable along the plurality of openings of the first
substrate and the slit of the second substrate.
18. The tiled device of claim 13, wherein: the second substrate
further has a plurality of openings; the first substrate further
has a slit formed below the plurality of openings of the second
substrate and gaps between the plurality of openings of the second
substrate; and the each force sensing devices further comprises: a
plurality of second electrodes formed on the second substrate and
coupled to the sensor array of the each force sensing device and
the controller through the gaps between the plurality of openings
of the second substrate; and a plurality of second insulation
layers formed between the second electrodes and the first substrate
across the slit of the first substrate, and between the plurality
of openings of the second substrate.
19. The tiled device of claim 13, wherein the each force sensing
device is foldable along the plurality of openings of the second
substrate and the slit of the first substrate.
20. The tiled device of claim 13, wherein the sensor array of the
each force sensing device is made of a piezoelectric material, a
piezoresistive material or a piezo-capacitive material.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The disclosure relates to force sensing devices, and in
particular, to a foldable force sensing device.
2. Description of the Prior Art
[0002] There has been a growing interest in providing frameless or
seamless array devices in recent years. An array device such as a
sensor array typically employs a considerable number of signal
lines to control operations of pixels in the sensor array.
Conventionally, these signal lines would take finite space at the
side regions of the array device to connect between an operational
array and a controller, resulting in a problem of designing a
frameless or seamless structure of the array device.
SUMMARY OF THE INVENTION
[0003] According to one embodiment of the invention, a force
sensing device includes a sensor array, a first substrate, a second
substrate and a plurality of electrodes. The first substrate has a
sensor region and a side region. The second substrate has a sensor
region and a side region. The sensor array is formed above the
sensor region of the first substrate. The plurality of electrodes
are formed on the sensor region and the side region of the first
substrate and below the sensor region and the side region of the
second substrate, and coupled to the sensor array. The side region
of the first substrate, the side region of the second substrate and
the plurality of electrodes on the side region are foldable to a
back side of the sensor array.
[0004] According to another embodiment of the invention, a tiled
device includes a controller and a plurality of force sensing
devices. The plurality of force sensing devices are tiled with each
other. Each force sensing device includes a sensor array. The
sensor array includes a matrix of pixels arranged at fixed vertical
intervals and at fixed horizontal intervals. The controller is
arranged at back sides of sensor arrays of the plurality of force
sensing devices, and is coupled to the plurality of force sensing
devices.
[0005] These and other objectives of the present invention will no
doubt become obvious to those of ordinary skill in the art after
reading the following detailed description of the preferred
embodiment that is illustrated in the various figures and
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIGS. 1A to 1C are schematic diagrams of a force sensing
device in an unfolded position according to an embodiment of the
invention.
[0007] FIG. 2 is a cross-sectional view of the force sensing device
in FIG. 1A along a line 2-2'.
[0008] FIG. 3 is a cross-sectional view of the force sensing device
in FIG. 1A along a line 3-3'.
[0009] FIG. 4 is a cross sectional view of the force sensing device
in FIG. 1A along a line 4-4'.
[0010] FIG. 5 is a schematic diagram of the force sensing device in
FIG. 1A in a folded position.
[0011] FIG. 6 is a cross-sectional view of the force sensing device
in FIG. 5 along a line 6-6'.
[0012] FIG. 7 is a cross-sectional view of the force sensing device
in FIG. 5 along a line 7-7'.
[0013] FIG. 8 is a cross-sectional view of a pixel of the sensor
array in FIG. 1A.
[0014] FIG. 9 is a schematic bottom view of a tiled device
according to an embodiment of the invention.
[0015] FIG. 10 is a schematic top view of the tiled device in FIG.
9.
DETAILED DESCRIPTION
[0016] FIG. 1A is a schematic diagram of a force sensing device 1
in an unfolded position according to an embodiment of the
invention. FIG. 1B is an enlarged view of a left side region of the
force sensing device 1. FIG. 1C is an enlarged view of a bottom
side region of the force sensing device 1. The force sensing device
1 may be arranged in a folded position or an unfolded position.
During semiconductor fabrication, the force sensing device 1 may be
formed in the unfolded position. Later, the force sensing device 1
may be folded in the folded position to form a seamless or
frameless device. A plurality of the seamless devices may be tiled
together along any edge of the seamless devices to form a larger
tiled device.
[0017] Referring to FIG. 1A, the force sensing device 1 may be a
pressure sensor, and may include a sensor array 10, a first
substrate 11, a second substrate 13, a plurality of first
electrodes 120 to 12N, a plurality of second electrodes 140 to 14M,
and a plurality of first insulation layers 150 to 15N, a plurality
of second insulation layers 170 to 17M and a controller, N, M being
positive integers, and N, M being identical to or different from
each other.
[0018] The first substrate 11 may have a sensor region and a side
region, the sensor region being the area of the first substrate 11
above which the sensor array 10 is formed, and the side region
being a side area of the first substrate 11 above which no sensor
array 10 is formed. The first electrodes 120 to 12N may be formed
on the sensor region and the side region of the first substrate 11.
The side region of the first substrate and the first electrodes 120
to 12N on the side region are foldable to a back side of the sensor
array 10, thereby forming a seamless structure when folded back.
Similarly, the second substrate 13 may have a sensor region and a
side region, the sensor region being the area of the second
substrate 13 below which the sensor array 10 is formed, and the
side region being a side area of the second substrate 13 below
which no sensor array 10 is formed. The second electrodes 140 to
14M may be formed on the sensor region and the side region of the
second substrate 13. The side region of the second substrate 13 and
the second electrodes 140 to 14M on the side region may be foldable
to the back side of the sensor array 10, thereby forming the
seamless structure when folded back. The first electrodes 120 to
12N on the sensor region of the first substrate 11 and the second
electrodes 140 to 14M on the sensor region of the second substrate
13 may be substantially perpendicular to each other.
[0019] The sensor array 10 may include an array of sensing pixels 8
arranged at fixed vertical intervals and at fixed horizontal
intervals to maintain a fixed sensor pitch between the sensing
pixels 8 along the vertical direction and the horizontal direction.
Each sensing pixel 8 may be made of a force sensitive material. In
one embodiment, N, M may both be 18, and the sensor array 10 may
include an array of 19.times.19 sensing pixels 8.
[0020] The first substrate 11 and the second substrate 13 may be
made of a rigid material, a flexible material or a combination
thereof. The first substrate 11 may have a thickness less than 200
um, and the second substrate 13 may have a thickness less than 200
um. The first electrodes 120 to 12N and the second electrodes 140
to 14M may be made of a conductive material such as a metal or an
alloy. The first substrate 11 may be a bottom substrate, and the
second substrate 13 may be a top substrate arranged above the first
substrate 11. The first electrodes 120 to 12N may be bottom
electrodes, and the second electrodes 140 to 14M may be top
electrodes.
[0021] Referring to FIG. 1B, on the left side region of the force
sensing device 1, the first substrate 11 may have a plurality of
openings 161 to 16N arranged in a column, the first electrodes 120
to 12N may be formed on the first substrate 11 and coupled to the
sensor array 10 through gaps between the plurality of openings 161
to 16N, the second substrate 13 may have a slit S1 formed above the
plurality of openings 161 to 16N and gaps between the plurality of
openings 161 to 16N, respectively, and the plurality of first
insulation layers 150 to 15N may be formed across the slit S1,
between the first electrodes 120 to 12N and the second substrate 13
and between the plurality of openings 161 to 16N, respectively. In
one example, a first insulation layer 15n may be formed across the
slit S1, between the first electrode 12n and the second substrate
13, and between the openings 16n and 16(n+1), n being a positive
integer between 1 and N-1. The plurality of first insulation layers
150 to 15N may prevent the first electrodes 120 to 12N from being
exposed to the external environment and ensure the normal
operations of the first electrodes 120 to 12N. The first electrodes
120 to 12N may be coupled to the sensor array 10 and the
controller, and the controller may detect a force applied to the
sensor array 10 according to signals delivered by the first
electrodes 120 to 12N. The force sensing device 1 is foldable along
the plurality of openings 161 to 16N and the slit S1. When being
folded, the plurality of openings 161 to 16N and the slit S1 may
effectively reduce a bending stress owing to the fold, resulting in
a compact and seamless structure, enhancing flexibility of tiling a
plurality of the force sensing devices 1, without affecting the
sensor pitch and operations of sensing pixels 8 in the proximity to
the fold and signal delivery of the first electrodes 120 to
12N.
[0022] Referring to FIG. 1C, on the bottom side region of the force
sensing device 1, the second substrate 13 may have a plurality of
openings 181 to 18M arranged in a row, the second electrodes 140 to
14M may be formed on the second substrate 13 and coupled to the
sensor array 10 and the controller through gaps between the
plurality of openings 181 to 18M, the first substrate 11 may have a
slit S2 formed below the plurality of openings 181 to 18M and gaps
between the plurality of openings 181 to 18M, respectively, and the
plurality of second insulation layers 170 to 17M may be formed
between the second electrodes 140 to 14M and the first substrate
11, across the slit S2, and between the plurality of openings 181
to 18M, respectively. In one example, a second insulation layer 17n
may be formed across the slit S2, between the second electrode 14n
and the first substrate 11, and between the openings 18m and
18(m+1), m being a positive integer between 1 and M-1. The
plurality of second insulation layers 170 to 17M may prevent the
second electrodes 140 to 14M from being exposed to the external
environment and ensure the normal operations of the second
electrodes 140 to 14M. The second electrodes 140 to 14M may be
coupled to the sensor array 10 and the controller, and the
controller may detect a force applied to the sensor array 10
according to signals delivered by the second electrodes 140 to 14M.
The force sensing device 1 is foldable along the plurality of
openings 181 to 18M and the slit S2. When being folded, the
plurality of openings 181 to 18M and the slit S2 may effectively
reduce a bending stress owing to the fold, resulting in a compact
and seamless structure, enhancing flexibility of tiling a plurality
of the force sensing devices 1, without affecting the sensor pitch
and operations of sensing pixels 8 in the proximity to the fold and
signal delivery of the second electrodes 140 to 14M.
[0023] While the plurality of openings 161 to 16N are formed
between all the first electrodes 120 to 12N in the force sensing
device 1, it would be appreciated that the plurality of openings
may also be formed between some of the first electrodes 120 to 12N
to meet specific design requirements. Likewise, while the plurality
of openings 181 to 18M are formed between all the second electrodes
140 to 14M in the force sensing device 1, it would be appreciated
that the plurality of openings may also be formed between some of
the second electrodes 140 to 14M to meet specific design
requirements.
[0024] FIG. 2 is a cross-sectional view of the force sensing device
1 along a line 2-2' in FIG. 1A. The cross-sectional view in FIG. 2
includes the first substrate 11, the first electrode 12n, the first
insulation layer 15n, the second substrate 13 and the slit S1 in
the unfolded position. The first substrate 11, the first electrode
12n, the first insulation layer 15n and the second substrate 13 are
sequentially stacked on each other from the bottom to the top. The
first electrode 12n is fabricated on a surface of the first
substrate 11 to secure the connection between the sensor array 10
and the controller. The first insulation layer 15n is deposited on
the first electrode 12n to prevent the first electrode 12n from
being exposed to the external environment and ensure proper signal
delivery of the first electrode 12n. The slit S1 is formed at the
second substrate 13 to relieve the bending stress when being
folded.
[0025] FIG. 3 is a cross-sectional view of the force sensing device
1 along a line 3-3' in FIG. 1A. The cross-sectional view in FIG. 3
includes the first substrate 11, the opening 16n, the second
substrate 13 and the slit S1 in the unfolded position. Since no
electrode passes through the this part of the force sensing device
1, the opening 16n is formed at the first substrate 11, and the
slit S1 is formed at the second substrate 13 to significantly
relieve the bending stress. The cross-sectional view at an opening
18m at the bottom side region of the force sensing device 1 in FIG.
1C may be similar to FIG. 3, except that the opening 16n is
replaced with the slit S2 and the slit S1 is replace with the
opening 18n, the configuration reduces the bending stress
considerably when the force sensing device 1 is folded along the
plurality of openings 181 to 18M and the slit S2.
[0026] FIG. 4 is a cross sectional view of the force sensing device
1 along a line 4-4' in FIG. 1A. The cross-sectional view in FIG. 4
includes the first substrate 11, the slit S2, the second insulation
layer 17m, the second electrode 14m and the second substrate 13 in
the unfolded position. The first substrate 11, the second
insulation layer 17m, the second electrode 14m and the second
substrate 13 are sequentially stacked on each other from the bottom
to the top. The slit S2 is formed at the first substrate 11 to
relieve the bending stress when being folded. The second insulation
layer 17m is deposited on the second electrode 14m to prevent the
second electrode 14m from being exposed to the external environment
and ensure proper signal delivery of the second electrode 14m. The
second electrode 14m is fabricated on a surface of the second
substrate 13 to secure the connection between the sensor array 10
and the controller.
[0027] FIG. 5 is a schematic diagram of the force sensing device 1
in a folded position, showing the first electrodes 120 to 12N, the
second electrodes 140 to 14M and the controller 50. Accordingly,
the first electrodes 120 to 12N may be folded back along the
plurality of openings 161 to 16N and the slit S1 to the back of the
force sensing device 1 and coupled to the controller 50. Likewise,
the second electrodes 140 to 14M may be folded back along the
plurality of openings 181 to 18M and the slit S2 to the back of the
force sensing device 1 and coupled to the controller 50. The
folding configuration ensures a compact and seamless structure,
ensuring proper operations of sensing pixels 8 in the proximity to
the fold and ensuring signal delivery of the first electrodes 120
to 12N and the second electrodes 140 to 14M, and enhancing
flexibility of tiling a plurality of the force sensing devices
1.
[0028] FIG. 6 is a cross-sectional view of the force sensing device
1 along a line 6-6' in FIG. 5. The cross-sectional view in FIG. 6
includes the first substrate 11, the first electrode 12n, the first
insulation layer 15n, the second substrate 13 and the slit S1 in
the folded position. When the force sensing device 1 is folded
along the plurality of openings 161 to 16N and the slit S1, the
slit S1 may be used to relieve the bending stress of the second
substrate 13 and the first insulation layer 15n may protect the
first electrode 12n from being exposed.
[0029] FIG. 7 is a cross-sectional view of the force sensing device
1 along a line 7-7' in FIG. 5. The cross-sectional view in FIG. 7
includes the first substrate 11, the slit S2, the second insulation
layer 17m, the second electrode 14m and the second substrate 13 in
the folded position. When the force sensing device 1 is folded
along the plurality of openings 181 to 18M and the slit S2, the
slit S2 may be used to relieve the bending stress of the first
substrate 11 and the first insulation layer 17m may protect the
second electrode 14m from being exposed.
[0030] FIG. 8 is a cross-sectional view of a sensing pixel 8 of the
sensor array 10. The sensing pixel 8 includes the first substrate
11, the first electrode 12n, the force sensitive material 80, the
second electrode 14m, the second substrate 13 and adhesion 82. The
first substrate 11, the first electrode 12n, the force sensitive
material 80, the second electrode 14m, the second substrate 13 are
sequentially stacked on each other. The adhesion 82 may adhere
between the first substrate 11 and the second substrate 13. The
force sensitive material 80 may be made of a piezoelectric
material, a piezoresistive material or a piezo-capacitive
material.
[0031] FIG. 9 is a schematic bottom view of a tiled device 9
according to an embodiment of the invention, and FIG. 10 is a
schematic top view of the tiled device 9. Four force sensing
devices 1 are tiled together to form the tiled device 9. The first
electrodes 120 to 12N and the second electrodes 140 to 14M of the
four force sensing devices 1 may be coupled to the same controller
or different controllers. Since the first electrodes 120 to 12N and
the second electrodes 140 to 14M of each force sensing device 1 are
folded back to provide the seamless structure, the size of the
tiled device 9 is not limited to the routing areas of the first
electrodes 120 to 12N and the second electrodes 140 to 14M, and may
be expanded along any direction and to any desired size. The
plurality of pixels in each force sensing device 1 are arranged
into a matrix at fixed vertical intervals wv and at fixed
horizontal intervals wh. Each of the force sensing devices 1 is
folded back along the respective openings 161 to 16M and slit S2
and along the respective openings 181 to 18M and slit S2, adjacent
pixels between vertically adjacent force sensing array devices 1 of
the plurality of force sensing devices are arranged at the fixed
vertical intervals wv, and adjacent pixels between horizontally
adjacent force sensing array devices 1 of the plurality of force
sensing devices are arranged at the fixed horizontal intervals wh,
resulting in a fixed pitch between adjacent pixels of the tiled
device 9 along the vertical direction and the horizontal direction,
regardless of the pixels being in the proximity to the edge or the
center of the force sensing devices 1. Further, while 2.times.2
sensor tiles are employed in the embodiment, other shapes and sizes
of the tiled device may also be implemented using the seamless
structure of the force sensing device 1.
[0032] While the first electrodes 120 to 12N and the second
electrodes 140 to 14M in FIGS. 1A to 1C, 5 and 8 are collected at
the central part of the side regions, it would be appreciated that
the first electrodes 120 to 12N and the second electrodes 140 to
14M may also be collected at one end of the side regions without
interfering with each other when folded. For example, the first
electrodes 120 to 12N may be collected at the top end of the left
side region and the second electrodes 140 to 14M may be collected
at the right end of the bottom side region. In this manner, the
first electrodes 120 to 12N and the second electrodes 140 to 14M
may not interfere with each other when folded, while delivering the
desired seamless structure.
[0033] While the force sensing device 1 has been implemented as a
sensor device, those skilled in the art would appreciate that by
applying the similar principle the foldable structure of the force
sensing device 1 may be adopted in other frameless devices or tiled
devices, e.g., a frameless display device or a tiled display
device.
[0034] The various embodiments of the force sensing device 1 in
FIGS. 1A to 1C, 2 to 6 provide a compact and seamless device
structure while ensuring proper operations of sensing pixels 8 in
the proximity to the fold and ensuring proper signal delivery of
the first electrodes 120 to 12N and the second electrodes 140 to
14M, and enhancing the flexibility of tiling a plurality of the
force sensing devices 1.
[0035] Those skilled in the art will readily observe that numerous
modifications and alterations of the device and method may be made
while retaining the teachings of the invention. Accordingly, the
above disclosure should be construed as limited only by the metes
and bounds of the appended claims.
* * * * *