TW202215674A - Sensing device, humidity sensing chip and method of manufacturing the device - Google Patents

Abstract

This invention provides a humidity sensing chip including a substrate, an insulation layer and a sensing material. The substrate has a lower substrate surface and a upper substrate surface corresponding to the lower substrate surface. The insulation layer is arranged on the upper substrate surface, has a plurality of spacings. a lower insulation layer surface and an upper insulation layer surface. The sensing material is arranged in the plurality of spacings, characterized in that the lower insulation layer surface corresponding to the plurality of spacings is hollowed out, so as to let the sensing material sense a humility of an environment from the upper insulation layer surface to the lower insulation layer surface.

Description

Sensing device, humidity sensing chip, and manufacturing method thereof

The present invention relates to a sensing device, a humidity sensing chip, and a manufacturing method thereof, and in particular, to a horizontally arranged sensing device, a humidity sensing chip, and a manufacturing method thereof.

In recent years, due to the booming development of wearable devices and smart electronic devices, many sensors are fabricated into bare die using Micro-electro-mechanical System (MEMS) technology, integrated into the sensing chip, and integrated into the sensing chip. In these devices, combined with the Internet of Things, all mobile devices will communicate with each other through the cloud to share data.

In the prior art, the humidity sensing unit can be divided into resistive type and capacitive type according to different electrical measurement methods. The resistive relative humidity sensing unit uses interdigitated electrodes as relative humidity sensing elements, and the electrode structure is relatively simple in design, low in cost, long-term stability and easy to calibrate. Most of the moisture-sensing materials used for humidity sensing use the porous characteristics of nano-scale materials, which have easier water absorption and higher specific surface area, which can improve the signal size, linearity, and response time, etc. However, resistive measurements It is easily affected by temperature and causes signal drift, so resistive sensing mechanisms are usually only used for low-priced humidity sensing units.

Generally speaking, there are two ways to configure the electrodes of the capacitive humidity sensing unit, one is the fork-shaped electrodes arranged on the same plane, and the other is the parallel plate electrodes arranged on different planes. A dielectric material with water absorption capability is introduced to sense the change in capacitance between the interdigitated electrodes or the parallel plate electrodes, and the humidity can be known by measuring the change in capacitance. There is another cantilever type humidity sensing unit, which uses a water-absorbing dielectric material as the cantilever, and senses the humidity change on the upper surface of the cantilever in response to the change of humidity, and generates different tensions on the upper surface of the cantilever, resulting in the bending of the cantilever. This also measures capacitance variation. For example, such a cantilevered humidity sensing unit is mentioned in the related papers on humidity sensors published by Chia-Yen Lee and Gwo-Bin Lee of Pingtung University of Science and Technology in Vol.3, 1-14, 2005.

The air pressure sensing unit can also be divided into resistive type and capacitive type. The resistive air pressure sensing unit is used to measure the voltage change through the change of the resistance value of the piezoresistive material when it is subjected to pressure deformation, and then through the circuit design such as the Wheatstone bridge to measure the voltage change. Elements usually have the advantage of high sensitivity, for example in Journal of Mechanical Sceience and Technology (KSME Int.J.), Vol.20, No.4, pp.505~512, 2006, by Jongwa Won, Sung-Hoon Choa, Zhao In the literature published by Yulong, a piezoresistive air pressure sensing unit with a bulk cavity is disclosed. A silicon diaphragm is arranged above the bulk cavity, and a piezoresistive material is arranged above the silicon diaphragm. The midpoint of the four sides of the cavity enables the piezoelectric material to be more sensitively deformed by the pressure of the ambient air pressure, so as to enhance its sensing sensitivity. But electricity Resistive elements are easily affected by temperature, and because the resistive elements need to pass through a rated current for sensing, the energy consumption is relatively serious.

The capacitive air pressure sensing unit measures by changing the overlapping area between the parallel plate capacitors or the relative distance between the upper and lower capacitive plates (or the upper and lower thin film electrodes). There is the problem of parasitic capacitance, but at present, integrated circuits are designed to minimize the influence of noise generated by parasitic capacitance, and the use of capacitive sensing mechanism usually consumes less energy, and the performance of sensitivity is not inferior. The most common sensing method at present is the sensing method using the change of the distance between the upper and lower capacitive plates.

The temperature sensing unit can be measured by using a resistor. For example, a long-wound metal wire is used as a resistor. The structure is relatively simple. When the temperature changes, the output voltage changes due to the change of the resistance value of the resistor. The temperature can be measured.

However, the reaction time between the sensing material on the current humidity sensing unit and the moisture in the external environment is very slow, and the sensitivity of the current air pressure sensing unit to detect the air pressure in the external environment needs to be improved

In view of the deficiencies in the prior art, the applicant of this case, after careful testing and research, and a spirit of perseverance, finally conceived of this case, which was able to overcome the deficiencies of the prior art. The following is a brief description of the case.

The present invention can effectively solve the above-mentioned problems of the prior art, and provides a horizontally arranged multi-sensing device, which implements a capacitive humidity sensing unit, a capacitive air pressure sensing unit, and a temperature sensing unit in a wafer-level manner. wafer The process uses a standard integrated circuit process, which can effectively reduce the size of the sensing device to the millimeter scale, and use a standard integrated circuit process platform to build these sensing units, which can effectively speed up the response time of the humidity sensing unit, And increase the sensitivity of the air pressure sensing unit. With the multi-layer stacking feature of the standard integrated circuit process, multiple measurement units can be easily fabricated in a single process. In addition, since the sensor chip can be fabricated using a commercialized process, it has a high process yield and reliability, and does not need to customize a special wafer process, and has the potential for mass production and commercialization. It can be seen that the present invention has extremely high industrial application value.

An idea of the present application is to provide the sensing device, which includes a semiconductor substrate, a carrier board, an air pressure sensing unit, a humidity sensing unit, and a temperature sensing unit. The semiconductor substrate has a first material portion, a second material portion, and a third material portion. The gas pressure sensing unit is coupled to the first material portion and includes a first electrode layer, a cavity, and a second electrode layer to form a gas pressure capacitor. The cavity is disposed between the first electrode layer and the carrier to form a closed space with a fluid, wherein the first material portion has a first open back cavity, the first open back cavity and the carrier The plate forms the cavity, and two sides of the first electrode layer each have a groove outside the closed space to reduce the rigidity of the first electrode layer. The humidity sensing unit is coupled to the second material portion, and has a columnar electrode stack layer forming a plurality of spaced spaces and an interdigitated configuration, and a sensing material disposed in the plurality of spaced spaces, wherein the second material A part has a second open back cavity, and the carrier plate has an opening at the position of the second open back cavity, so as to increase a contact area of the humidity sensing unit. The temperature sensing unit is coupled to the third material portion, wherein the temperature sensing unit includes a P-type semiconductor region and an N-type semiconductor region to form a diode element; wherein: the humidity sensing unit is And the air pressure sensing unit has a first capacitor and a second capacitor respectively. The sensing material has a dielectric constant. The humidity sensing unit senses the first capacitance to generate a the first capacitive sensing signal. There is a gap between the first electrode layer and the second electrode layer. Under the condition that the first electrode layer is deformed to change the distance to cause the second capacitance to change, the air pressure sensing unit senses the second capacitance to generate a second capacitance sensing signal.

One concept of the present application is to provide a humidity sensing chip, which includes a substrate, an insulating layer, and a sensing material. The substrate has a lower surface of the substrate and an upper surface of the substrate opposite to the lower surface of the substrate. The insulating layer is disposed on the upper surface of the substrate, and has a plurality of accommodating spaces, a lower surface of the insulating layer, and an upper surface of the insulating layer. The sensing material is disposed in the plurality of accommodating spaces, and it is characterized in that a portion of the lower surface of the insulating layer relative to the plurality of accommodating spaces is hollowed out, so that the sensing material can be removed from the upper surface of the insulating layer and under the insulating layer. The surface senses the humidity of an environment.

Another idea of the present application is to provide a method for manufacturing a sensing device, including the following steps: providing a pre-structure for forming a plurality of sensing units, wherein the pre-structure includes a substrate, a first electrode layer, A second electrode layer and a columnar electrode stack layer, and the substrate has a first material portion and a second material portion; etching a first sub-portion of the first material portion and a portion of the second material portion The second sub-section is used to form a first open back cavity and a second open back cavity respectively; the peripheral parts of the first electrode layer and the second electrode layer are etched so that each side of the first electrode layer has a trenches, and etching a portion of the columnar electrode stack layer to form a plurality of spacing spaces; filling a sensing material in the plurality of spacing spaces to form a semi-finished product of the sensing device; and combining the semi-finished product with a carrier board , respectively by using the The second material portion and the first material portion form a humidity sensing unit with a first capacitance and an air pressure sensing unit with a second capacitance, wherein the first electrode layer is flexible, and the two sides of the first electrode layer are flexible. Each of the grooves increases the flexibility, the first electrode layer measures the first capacitance according to a change in an ambient air pressure, the sensing material is used to sense a humidity of an environment, and the second open back The cavity accelerates a response time of the humidity sensing unit.

Another idea of the present application is to provide a sensing device, the sensing device includes a humidity sensing unit, the humidity sensing unit includes a front surface and a back surface opposite to the front surface, a sensing material, and an open back cavity . The sensing material is located on the front side, and the open back cavity is formed on the back side so that the sensing material senses a humidity of an environment from the open back cavity.

10,30: Sensing device

101: Air pressure sensing unit

20: Humidity Sensing Chip

102: Humidity sensing unit

DIO: Diode Component

103: Temperature sensing unit

103N: N-type semiconductor region

103P: P-type semiconductor region

100: Semiconductor substrate

1011: first electrode layer

1001: First Materials Section

1012: the second electrode layer

1003: Section III Materials

1002: Second Materials Section

1013: Cavity

CBC: closed back cavity

PARA: Second Area

1014: Gas pressure capacitors

TARA: first area

HARA: The third area

CAP1: first capacitor

CAP2: second capacitor

CREG: middle region

TH, TTH: groove

16: Semi-finished products

SH: Complex interval space

P: ambient air pressure

1021: Columnar electrode stack

OPNC1: First open back cavity

1022: Sensing Materials

OPNC2: Second open back cavity

OPN: Opening

1021-1: The first columnar electrode layer

1021-2: Second columnar electrode layer

TRH: through hole

STEM1, STEM2: temperature sensing signal

SCAP1: The first capacitive sensing signal

SCAP2: The second capacitive sensing signal

DIC: Dielectric Constant

MOI: Moisture

FLM: Film

FI: Finger Configuration

VTEP: Voltage

STEMP: temperature sensing signal

TEP: temperature

DEP1: The first depth

12: Carrier board

DEP2: Second Depth

14: Front structure

1001P: First Subsection

101P: Peripheral part

1002P: Second subsection

1021P: part of the stack of columnar electrodes

SC: Sensing chip

PAD: Complex connection pad

SL: plural signal lines

18: Airtight glue

200: Substrate

20: Humidity Sensing Chip

2022, 3022: Sensing Materials

2023: Insulation

200U: the upper surface of the substrate

200D: lower surface

2023D: Lower surface of insulating layer

SH: complex housing space

2023U: Top surface of insulating layer

2021E: Complex electrode area

302U: Sensing the front side of the material

302: Humidity Sensing Unit

302D: Sensing the back of the material

This case can be better understood by those skilled in the art through the following diagrams and detailed descriptions.

The first figure is a schematic diagram of a sensing device according to a preferred embodiment of the present disclosure.

The second figure is a schematic diagram of a method of manufacturing a sensing device according to a preferred embodiment of the present disclosure.

The third FIGS. A to E are schematic diagrams of each manufacturing process of the sensing device according to the preferred embodiment of the present disclosure.

FIG. 4 is a schematic diagram of a curve of sensitivity and response time of the humidity sensing unit according to the preferred embodiment of the present disclosure.

FIG. 5 is a schematic diagram of the sensitivity curve of the air pressure sensing unit according to the preferred embodiment of the present disclosure.

FIG. 6 is a schematic diagram of a humidity sensing chip according to a preferred embodiment of the present disclosure.

FIG. 7 is a schematic diagram of a sensing device according to a preferred embodiment of the present disclosure.

Please read the following detailed description with reference to the accompanying drawings of the present disclosure, which are by way of example to introduce various embodiments of the present disclosure and to provide an understanding of how to implement the present invention. The embodiments of the present disclosure provide sufficient content for those skilled in the art to implement the embodiments of the present disclosure, or to implement embodiments derived from the contents of the present disclosure. It should be noted that these embodiments are not mutually exclusive, and some embodiments can be appropriately combined with one or more other embodiments to form new embodiments, that is, the implementation of the present disclosure is not limited to Examples disclosed below. In addition, for the sake of brevity and clarity, the relevant details are not excessively disclosed in each embodiment, and even if specific details are disclosed, they are only exemplified to make the readers understand, and the relevant specific details in the various embodiments are not intended to be limiting. disclosure of the case.

Please refer to the first figure, which is a schematic diagram of the sensing device 10 according to the disclosed preferred embodiment. Please refer to the three-dimensional view and the cross-sectional view in the first figure. The sensing device 10 includes a semiconductor substrate 100 , a carrier board 12 , an air pressure sensing unit 101 , a humidity sensing unit 102 , and a temperature sensing unit 103. The semiconductor substrate 100 is not yet coupled to the carrier 12 in the perspective view, while the semiconductor substrate 100 is already coupled to the carrier 12 in the cross-sectional view. The semiconductor substrate 100 has a first material portion 1001 , a second material portion 1002 , and a third material portion 1003 . The gas pressure sensing unit 101 is coupled to the first material portion 1001 , and includes a first electrode layer 1011 , a cavity 1013 , and a second electrode layer 1012 , to form a gas pressure capacitor 1014 . The cavity 1013 is disposed between the first electrode layer 1011 and the carrier plate 12 to form a closed space with a fluid, wherein the first material portion 1001 has a first open back cavity OPNC1, the first open The back cavity OPNC1 and the carrier 12 form the cavity 1013, the first Two sides of the electrode layer 1011 each have a trench TH outside the closed space to reduce the rigidity 1011 of the first electrode layer. The humidity sensing unit 102 is coupled to the second material portion 1002 and has a columnar electrode stack 1021 forming a plurality of spaced spaces SH and an interdigitated arrangement FI, and a sensing material disposed in the plurality of spaced spaces SH 1022, wherein the second material portion 1002 has a second open back cavity OPNC2, and the carrier 12 has an opening OPN at the second open back cavity OPNC2, so as to increase a contact area of the humidity sensing unit 102 ARA. The semiconductor substrate 100 in the three-dimensional view has not yet been processed, and therefore does not yet have the first open back cavity OPNC1 and the second open back cavity OPNC2, while in the cross-sectional view the semiconductor substrate 100 has been processed to form the first open back cavity OPNC1 and the second open back cavity OPNC2 The open back cavity OPNC1 and the second open back cavity OPNC2 are also processed to form the opening OPN. The temperature sensing unit 103 is coupled to the third material portion 1003, wherein the temperature sensing unit 103 includes a P-type semiconductor region 103P and an N-type semiconductor region 103N to form a diode element DIO; wherein: the humidity The sensing unit 102 and the air pressure sensing unit 101 respectively have a first capacitor CAP1 and a second capacitor CAP2. The sensing material 1022 has a dielectric constant DIC. Under the condition that the sensing material 1022 changes the dielectric constant DIC by releasing its moisture MOI or absorbing moisture MOI in the air to cause the first capacitance CAP1 to change, the humidity sensing unit 101 senses the The first capacitor CAP1 generates a first capacitance sensing signal SCAP1. There is a spacing SP between the first electrode layer 1011 and the second electrode layer 1012 . Under the condition that the first electrode layer 1011 is deformed to change the spacing SP to cause the second capacitance CAP2 to change, the air pressure sensing unit 101 senses the second capacitance CAP2 to generate a second capacitance sensing signal SCAP2.

In any embodiment of the present disclosure, such as in the first figure, the third material portion 1003 may partially overlap the first material portion 1001 and the second material portion 1002 . When the sensing device 10 is fabricated by processing a silicon wafer, the first open back cavity OPNC1 is connected to the The second open back cavity OPNC2 is formed by etching the first material portion 1001 and the second material portion 1002 of the semiconductor substrate 100 respectively, wherein the cavity 1013 is a closed back cavity CBC of the air pressure sensing unit 103 . When the sensing device 10 is fabricated by dicing the silicon wafer into a plurality of dies, the first open back cavity OPNC1 and the second open back cavity OPNC2 are respectively drilled through the semiconductor substrate by laser The first material portion 1001 and the second material portion 1002 of 100 are formed. The trenches TH on both sides of the first electrode layer 1011 increase a sensitivity of the gas pressure capacitor 1014 . An air pressure P sensed by the air pressure sensing unit 101 is proportional to the second capacitor CAP2, wherein the air pressure P is an ambient air pressure. The ambient air pressure P deforms a middle region CREG of the first electrode layer 1011 . A humidity sensed by the humidity sensing unit 102 is proportional to the first capacitor CAP1. The columnar electrode stack layer 1021 includes a first columnar electrode layer 1021-1 and a second columnar electrode layer 1021-2 forming an interdigitated configuration FI with the first columnar electrode layer 1021-1, and the Each electrode layer of the first columnar electrode layer 1021-1 and each electrode layer of the second columnar electrode layer 1021-2 are electrically connected to each other through a through hole TRH. The sensing material 1022 is a polyimide (Polymide, PI). There is a thin film FLM between the sensing material 1022 and the columnar electrode stack layer 1021 to prevent moisture MOI or other corrosive gases from eroding the columnar metal stack layer 1021, wherein the thin film FLM is parylene ( Parylene C) film.

In any embodiment of the present disclosure, the sensing device 10 may be a sensing chip with a plurality of sensing units 101 , 102 , 103 arranged horizontally and having a temperature TEP. For example, in the first figure, there is a trench TTH above the diode element DIO to sense the temperature TEP. The diode element DIO forms a voltage VTEP in response to the temperature TEP, and the temperature sensing unit 103 senses the voltage to generate a temperature sensing signal STEMP, wherein the temperature TEP and the voltage VTEP have an inverse relationship, which It is related to the temperature and voltage curve of the diode element DIO. The temperature sensing unit 103 There is a first area TARA, the air pressure sensing unit 101 has a second area PARA, the humidity sensing unit 102 has a third area HARA, the second area PARA is approximately equal to the third area HARA, and the first area An area TARA is much smaller than each of the second area PARA and the third area HARA. The temperature sensing unit 103 is disposed near the air pressure sensing unit 101 or the humidity sensing unit 102 and is not subject to an ambient air pressure P measured by the air pressure sensing unit 101 or the humidity sensing unit 102 Affected by ambient humidity.

Please refer to the second figure, which is a schematic diagram of a method S10 of manufacturing a sensing device 10 according to a preferred embodiment of the present disclosure, and please refer to the third FIG. A to FIG. Schematic diagram of each manufacturing process. Please refer to the first figure, the second figure, and the third figure A to the third figure E. The method S10 includes the following steps: Step S101, providing a pre-structure 14 for forming the plurality of sensing units 101, 102, 103, wherein the The front structure 14 includes a substrate 100 , a first electrode layer 1011 , a second electrode layer 1012 and a columnar electrode stack layer 1021 , and the substrate 100 has a first material portion 1001 and a second material portion 1002. Step S102, etching a first sub-portion 1001P of the first material portion 1001 and a second sub-portion 1002P of the second material portion 1002 to form a first open back cavity OPNC1 and a second open back cavity OPNC2, respectively . Step S103 , etching the peripheral portion 101P of the first electrode layer 1011 and the second electrode layer 1012 so that each side of the first electrode layer 1011 has a trench TH, and etching one of the columnar electrode stack layers 1021 part 1021P to form a complex space SH. In step S104 , a sensing material 1022 is filled in the plurality of spaced spaces SH to form the semi-finished product 16 of the sensing device 10 . Step S105, combining the semi-finished product 105 and a carrier board 12 to form a humidity sensing unit 102 having a first capacitor CAP1 and a first A pressure sensing unit 101 with two capacitors CAP2, wherein the first The electrode layer 1011 has a flexibility, and the grooves TH on both sides of the electrode layer 1011 increase the flexibility. The first electrode layer 1011 measures the second capacitance CAP2 according to a change of an ambient air pressure P, and the sensing material 1022 It is used for sensing a humidity of an environment, and the second open back cavity OPNC2 accelerates a response time of the humidity sensing unit 102 .

In the above step S103, etching the peripheral portion 101P of the first electrode layer 1011 and the second electrode layer 1012 includes performing metal wet etching on the front and back sides of the wafer, so that each side of the first electrode layer 1011 has a groove The groove TH is etched, and a part 1021P of the columnar electrode stack layer 1021 is etched, which also includes metal wet etching on the front and back sides of the wafer, and the part 1021P includes an electrode column between the two columnar electrode columns.

In any of the embodiments of the present disclosure, if the bare die formed by dicing the wafer is used for processing, laser drilling may be used instead of etching, as shown in FIG. 3 F, which is the present disclosure. A schematic diagram of the substrate 100 using laser drilling in the preferred embodiment. For example, in FIG. 3 F, the first material portion 1001 and the second material portion 1002 are first drilled to a first depth DEP1 by laser, and then inductively coupled plasma etching (or ICP for short) is used , and then continue to etch to the second depth DEP2 as shown in the third figure B. The method S10 further includes the following steps: when the sensing device 10 is fabricated by processing a silicon wafer, the first open back cavity OPNC1 and the second open back cavity OPNC2 are respectively etched by etching the semiconductor substrate The first material portion 1001 and the second material portion 1002 of 100 are formed, wherein the cavity 1013 is a closed back cavity CBC of the air pressure sensing unit 103 . When the sensing device 10 is fabricated by dicing the silicon wafer into a plurality of dies, the first open back cavity OPNC1 and the second open back cavity OPNC2 are respectively drilled through the semiconductor substrate by laser The first material portion 1001 and the second material portion 1002 of 100 are formed.

In any embodiment of the present disclosure, please refer to the third FIG. E, the method S10 further includes the following steps: using laser drilling to form the plurality of connection pads PAD, and correspondingly connecting the plurality of signal lines SL to the a plurality of connection pads PAD; and the sensing chip SC is packaged on the carrier board 12 using an airtight glue 18 , wherein the carrier board 12 is a PCB board.

In any embodiment of the present disclosure, the substrate 100 is a semiconductor substrate. The columnar electrode stack layer 1021 includes a first columnar electrode layer 1021-1 and a second columnar electrode layer 1021-2 forming an interdigitated configuration FI with the first columnar electrode layer 1021-1, and the Each electrode layer of the first columnar electrode layer 1021-1 and each electrode layer of the second columnar electrode layer 1021-2 are electrically connected to each other through a through hole TRH. The first columnar electrode layer 1021-1 and the second columnar electrode layer 1021-2 are not only in a single plane, but are stacked three-dimensionally, thus increasing the working area between them, thereby increasing the first capacitance CAP1, to expand the measurement range of the humidity sensing unit 102 . The sensing material 1022 is a polyimide (Polymide, PI). There is a thin film FLM between the sensing material 1022 and the columnar electrode stack layer 1021 to prevent moisture MOI or other corrosive gases from eroding the columnar metal stack layer 1021, wherein the thin film FLM is parylene ( Parylene C) film.

In any embodiment of the present disclosure, the substrate 100 further has a third material portion 1003 , the sensing device 10 further includes a temperature sensing unit 103 , and the temperature sensing unit 103 is formed by using the substrate 100 The third material portion 1003 is formed with the third material portion 1003 partially overlapping the first material portion 1001 and the second material portion 1002, and the temperature sensing unit 103 includes a P-type semiconductor region 103P and An N-type semiconductor region 103N is formed to form a diode element DIO. The temperature sensing unit 103 is disposed near the air pressure sensing unit 101 or the humidity sensing unit 102 and is not subject to the ambient air pressure P measured by the air pressure sensing unit 101 or the humidity sensing unit 102 The humidity of the environment is affected.

Please refer to FIG. 4 , which is a schematic diagram illustrating a curve of sensitivity and response time of the humidity sensing unit 102 according to the preferred embodiment. The horizontal axis in the sensitivity graph represents the relative humidity of the environment, in percentage %, and the vertical axis represents the value of the first capacitor CAP1 measured by the humidity sensing unit 102, in pF, the relative humidity RH rises or When dropping a percentage, the capacitance value rises or falls by 5.45fF (1 femto Farad=10 ^-15 Farad). The horizontal axis in the graph of the response time represents the reaction time RT for the sensing material 1022 to absorb the moisture MOI in the external environment, in seconds, and the vertical axis represents the concentration of water molecules absorbed in the sensing material 1022, in per cubic meter Meter moles are the unit. Please refer to the first figure, the second figure, and the fourth figure at the same time, in any embodiment of the present disclosure, a humidity RH sensed by the humidity sensing unit 102 is in a proportional relationship with the first capacitor CAP1, the The method S10 further includes the following steps: the second open back cavity OPNC2 formed by using the second material portion 1002 is used to reduce a response time RT of the humidity sensing unit 102, from the humidity sensing in the fourth figure The response curve of the unit 102 shows that the response time RT1 of the humidity sensing unit 102 with the second open back cavity OPNC2 can reach the predetermined concentration of moisture MOI absorbed by the sensing material 1022 in about 5.5 seconds; The reaction time RT2 of the humidity sensing unit in the back cavity is about 26.6 seconds to reach the predetermined concentration of the moisture MOI absorbed by the sensing material 1022 , which reduces the reaction time quite significantly.

Please refer to FIG. 5 , which is a schematic diagram illustrating a sensitivity curve of the air pressure sensing unit 101 according to the preferred embodiment. The horizontal axis represents the ambient air pressure P, and the unit is kPa, and the vertical axis represents the capacitance change value measured by the air pressure sensing unit 101 in response to the change of the ambient air pressure P, and the unit is Pf. Please refer to the first and fifth figures together, an air pressure P sensed by the air pressure sensing unit 101 is proportional to the second capacitor CAP2, wherein the air pressure P is an ambient air pressure P. The ambient air pressure P deforms a middle region CREG of the first electrode layer 1011 . on both sides of the first electrode layer 1011 Each of the trenches TH on both sides of the first electrode layer 1011 increases a sensitivity PS of the gas pressure capacitor 1014, and the sensitivity PS is about 0.79fF/kPa. Since the trenches TH on both sides of the first electrode layer 1011 reduce the sensitivity of the first electrode layer 1011 The rigidity on both sides of the first electrode layer 1011 increases the flexibility of a middle region CREG of the first electrode layer 1011, making it easier to deform, so that a good sensitivity of 0.79Ff/kPa can be achieved.

Please refer to FIG. 6 , which is a schematic diagram of the humidity sensing chip 20 according to the preferred embodiment of the disclosure. Please refer to the perspective view and cross-sectional view in Figure 6 together. The substrate 200 is not yet coupled to the carrier board 22 in the perspective view, while the substrate 200 is already coupled to the carrier board 22 in the cross-sectional view. The humidity sensing chip 20 includes a substrate 200 , an insulating layer 2023 , and a sensing material 2022 . The substrate 200 has a lower surface 200D and a substrate upper surface 200U opposite to the lower surface 200D. The insulating layer 2023 is disposed on the upper surface 200U of the substrate, and has a plurality of accommodating spaces SH, an insulating layer lower surface 2023D, and an insulating layer upper surface 2023U. The sensing material 2022 is disposed in the plurality of accommodating spaces SH, and is characterized in that the portion of the lower surface 2023D of the insulating layer relative to the plurality of accommodating spaces SH is hollowed out, so that the sensing material 2022 can be removed from the upper surface of the insulating layer 2023U and the lower surface 2023D of the insulating layer sense a humidity RH of an environment.

In the perspective view of the sixth figure, the substrate 200 has not yet been processed, so it does not yet have the second open back cavity OPNC2, while in the cross-sectional view, the substrate 200 has been processed to form the second open back cavity OPNC2, and the carrier board 22 The opening OPN is also formed after processing. In any embodiment of the present disclosure, the plurality of accommodating spaces SH in the insulating layer 2023 has a plurality of electrode regions 2021E, and the portion of the substrate 200 relative to the plurality of electrode regions 2021E is also hollowed out.

The humidity sensing chip 20 in the sixth figure can be applied and integrated in the sensing device 10 in the first figure, and is arranged horizontally with the air pressure sensing unit 101 and the temperature sensing unit 103 to form various types of sensing devices, The sensing device formed by the combination of each other can be referred to the above, so it is not necessary to Repeat.

In any embodiment of the present disclosure, the substrate 200 is a semiconductor substrate having a second material portion 2002 . The substrate 200 of the sensing chip 20 is combined with a carrier board 22 . The humidity sensing unit 202 is coupled to the second material portion 2002 . The sensing chip 20 is a sensing chip with a plurality of sensing units arranged horizontally. The humidity sensing unit 202 has a columnar electrode stack 2021 forming a plurality of spaced spaces SH and an interdigitated arrangement FI, and a sensing material 2022 disposed in the plurality of spaced spaces SH, wherein the second portion of the semiconductor substrate The material portion 2002 has a second open back cavity OPNC2 , and the carrier plate 22 has an opening OPN at the second open back cavity OPNC2 to increase a contact area HARA of the humidity sensing unit 202 . The humidity sensing unit 202 has a first electrical parameter. The first electrical parameter is a first capacitor CAP1. The sensing material 2022 has a dielectric constant DIC. Under the condition that the sensing material 2022 changes the dielectric constant DIC by releasing its moisture MOI or absorbing moisture MOI in the air to cause the first capacitance CAP1 to change, the humidity sensing unit 202 senses the the first capacitor CAP1 to generate a first capacitance sensing signal SCAP1.

Please refer to FIG. 7 , which is a schematic diagram of the sensing device 30 according to the disclosed preferred embodiment. The sensing device 30 includes a humidity sensing unit 302. The humidity sensing unit 302 includes a front surface 302U, a back surface 302D opposite to the front surface 302U, a sensing material 3022, and an open back cavity OPNC2. The sensing material 3022 is located on the front surface 302U, and the open back cavity OPNC2 is formed on the back surface 302D so that the sensing material 3022 senses a humidity RH in an environment from the open back cavity OPNC2. Please refer to the first figure and the seventh figure together, the sensing device 30 in the seventh figure only illustrates the humidity sensing unit 301, and others may also include the air pressure sensing unit 101, and the temperature sensing unit 103 to form another embodiment, and thus will not be repeated.

The invention proposed in this case will be fully understood from the description of the above-mentioned embodiments, so that those with ordinary knowledge in the technical field can complete it accordingly. However, the implementation of this case is not limited by the following embodiments. Those with ordinary knowledge in the technical field can still deduce other embodiments according to the spirit of the disclosed embodiments, and these embodiments should all belong to the scope of the present invention.

The present invention is a difficult innovative invention with profound industrial value, and an application is filed in accordance with the law. The present invention can be modified in various ways by people who are familiar with the art, but it does not deviate from the protection of the scope of the appended patent application.

20: Humidity Sensing Chip

200: Substrate

2023: Insulation

2022: Sensing Materials

200D: lower surface

200U: the upper surface of the substrate

SH: complex housing space

2023D: Lower surface of insulating layer

2023U: Top surface of insulating layer

Claims (10)

A sensing device, comprising: a semiconductor substrate having a first material portion, a second material portion, and a third material portion; a carrier board coupled to the semiconductor substrate; A gas pressure sensing unit coupled to the first material portion and comprising a first electrode layer, a cavity, and a second electrode layer to form a gas pressure capacitor, the cavity is disposed on the first electrode layer and the carrier to form a closed space with a fluid, wherein the first material portion has a first open back cavity, the first open back cavity and the carrier form the cavity, the first electrode Each side of the layer has a groove outside the closed space to reduce the rigidity of the first electrode layer; A humidity sensing unit coupled to the second material portion and having a columnar electrode stack layer forming a plurality of spaced spaces and an interdigitated configuration, and a sensing material disposed in the plurality of spaced spaces, wherein the second The material portion has a second open back cavity, and the carrier plate has an opening at the second open back cavity to increase a contact area of the humidity sensing unit; and A temperature sensing unit coupled to the third material portion, wherein the temperature sensing unit includes a P-type semiconductor region and an N-type semiconductor region to form a diode element; wherein: The humidity sensing unit and the air pressure sensing unit respectively have a first capacitor and a second capacitor; the sensing material has a dielectric constant; and Under the condition that the sensing material changes the dielectric constant by releasing its moisture or absorbing moisture in the air to cause the first capacitance to change, the humidity sensing unit senses the first capacitance to generate a A first capacitance sensing signal is generated. There is a distance between the first electrode layer and the second electrode layer; and Under the condition that the first electrode layer is deformed to change the distance to cause the second capacitance to change, the air pressure sensing unit senses the second capacitance to generate a second capacitance sensing signal. The sensing device of claim 1, wherein: the third material portion partially overlaps the first material portion and the second material portion; When the sensing device is fabricated by processing a silicon wafer, the first open back cavity and the second open back cavity are formed by etching the first material portion and the second material of the semiconductor substrate, respectively partially formed, wherein the cavity is a closed back cavity of the air pressure sensing unit; When the sensing device is fabricated by dicing the silicon wafer into a plurality of dies, the first open back cavity and the second open back cavity are respectively drilled by a laser on the first and second portions of the semiconductor substrate. A material portion is formed with the second material portion; The grooves on both sides of the first electrode layer increase a sensitivity of the gas pressure capacitor; An air pressure sensed by the air pressure sensing unit is proportional to the second capacitance, wherein the air pressure is an ambient air pressure; the ambient air pressure deforms a middle region of the first electrode layer; A humidity sensed by the humidity sensing unit is proportional to the first capacitance; The columnar electrode stack layer includes a first columnar electrode layer and a second columnar electrode layer that forms an interdigitated configuration with the first columnar electrode layer, and each electrode layer of the first columnar electrode layer and between each electrode layer of the second columnar electrode layer are electrically connected to each other through a through hole; The sensing material is a polyimide (PI); and There is a thin film between the sensing material and the columnar electrode stack layer to prevent moisture or other corrosive gases from eroding the columnar metal stack layer, wherein the thin film is a Parylene C thin film. The sensing device of claim 1, wherein: The sensing device is a sensing chip with a plurality of sensing units arranged horizontally, and has a temperature; The diode element forms a voltage in response to the temperature, and the temperature sensing unit senses the voltage to generate a temperature sensing signal, wherein the temperature has an inverse relationship with the voltage; The temperature sensing unit has a first area, the air pressure sensing unit has a second area, the humidity sensing unit has a third area, the second area is approximately equal to the third area, and the first area is substantially smaller than each of the second area and the third area; and The temperature sensing unit is disposed near the air pressure sensing unit or the humidity sensing unit, and is not affected by an ambient air pressure measured by the air pressure sensing unit or an ambient humidity of the humidity sensing unit. A method of manufacturing a sensing device, comprising the following steps: A pre-structure for forming a plurality of sensing units is provided, wherein the pre-structure comprises a substrate, a first electrode layer, a second electrode layer and a columnar electrode stack layer, and the substrate has a first a material portion and a second material portion; etching a first sub-portion of the first material portion and a second sub-portion of the second material portion to form a first open back cavity and a second open back cavity, respectively; Etching the peripheral portions of the first electrode layer and the second electrode layer, so that each side of the first electrode layer has a groove, and etching a part of the columnar electrode stack layer to form a plurality of spacing spaces; Filling a sensing material in the plurality of spaced spaces to form a half-finished product of the sensing device; and combining the semi-finished product and a carrier to form a humidity sensing unit with a first capacitor and an air pressure sensing unit with a second capacitor by using the second material portion and the first material portion, respectively, The first electrode layer has a flexibility, the grooves on both sides of the first electrode layer increase the flexibility, the first electrode layer measures the first capacitance according to a change of an ambient air pressure, and the sensing material is used for A humidity of an environment is sensed, and the second open back cavity accelerates a response time of the humidity sensing unit. A method as claimed in claim 4, wherein: The substrate is a semiconductor substrate, and the sensing device is a sensing chip having a plurality of signal lines and a plurality of connection pads corresponding to the plurality of signal lines; The method further includes the following steps: using laser drilling to form the plurality of connection pads, and respectively connecting the plurality of signal lines to the plurality of connection pads; and using an airtight glue to package the sensing chip on the carrier board, wherein the carrier board is a PCB board; The method further includes the following steps: When the sensing device is fabricated by processing a silicon wafer, the first open back cavity and the second open back cavity are formed by etching the first material portion and the second material portion of the substrate, respectively formed; and When the sensing device is fabricated by dicing the silicon wafer into a plurality of dies, the first open back cavity and the second open back cavity are respectively drilled by a laser on the first portion of the substrate. material department formed by dispensing the second material portion; The grooves on both sides of the first electrode layer increase a sensitivity of the gas pressure capacitor; An air pressure sensed by the air pressure sensing unit is proportional to the second capacitance, wherein the air pressure is an ambient air pressure; the ambient air pressure deforms a middle region of the first electrode layer; The substrate is a semiconductor substrate; The method further includes the following steps: The second open back cavity formed by using the second material portion is used to reduce a response time of the humidity sensing unit; A humidity sensed by the humidity sensing unit is proportional to the first capacitance; The columnar electrode stack layer includes a first columnar electrode layer and a second columnar electrode layer that forms an interdigitated configuration with the first columnar electrode layer, and each electrode layer of the first columnar electrode layer and between each electrode layer of the second columnar electrode layer are electrically connected to each other through a through hole; The sensing material is a polyimide (Polymide, PI); There is a thin film between the sensing material and the columnar electrode stack layer to prevent moisture or other corrosive gases from eroding the columnar metal stack layer, wherein the thin film is a Parylene C thin film; The substrate also has a third material portion, and the sensing device further includes a temperature sensing unit formed by using the third material portion of the substrate, the third material portion and the The first material portion and the second material portion partially overlap, and the temperature sensing unit includes a P-type semiconductor region and an N-type semiconductor region to form a diode element; and The temperature sensing unit is disposed near the air pressure sensing unit or the humidity sensing unit, and is not affected by the ambient air pressure measured by the air pressure sensing unit or the humidity of the environment of the humidity sensing unit Influence. A humidity sensing chip, comprising: a substrate having a lower surface of the substrate and an upper surface of the substrate opposite to the lower surface of the substrate; an insulating layer disposed on the upper surface of the substrate and having a plurality of accommodating spaces, a lower surface of the insulating layer, and an upper surface of the insulating layer; and A sensing material disposed in the plurality of accommodating spaces, characterized in that a portion of the lower surface of the insulating layer relative to the plurality of accommodating spaces is hollowed out, so that the sensing material can be removed from the upper surface of the insulating layer and the insulating layer The lower surface senses a humidity of an environment. The humidity sensing wafer of claim 6, wherein: The plurality of accommodating spaces in the insulating layer have a plurality of electrode regions, and the portion of the substrate relative to the plurality of electrode regions is also hollowed out; the substrate is a semiconductor substrate having a second material portion; The substrate of the sensing chip is combined with a carrier; the humidity sensing unit is coupled to the second material portion; The sensing device is a sensing chip with a plurality of sensing units arranged horizontally; The air pressure sensing unit includes the indicating medium, the cavity, and a second electrode layer, the indicating medium is a first electrode layer, and the cavity is disposed between the first electrode layer and the carrier, and forming a closed space with a fluid, wherein outside the closed space and on both sides of the first electrode layer, there is a groove outside the closed space, so as to reduce the rigidity of the first electrode layer; The humidity sensing unit has a stack of columnar electrodes forming a plurality of spaced spaces and an interdigitated configuration layer, and a sensing material disposed in the plurality of spaced spaces, wherein the second material portion of the semiconductor substrate has a second open back cavity, and the carrier has an opening in the place of the second open back cavity , to increase a contact area of the humidity sensing unit; The humidity sensing unit has a first electrical parameter, and the first electrical parameter is a first capacitor; the sensing material has a dielectric constant; and Under the condition that the sensing material changes the dielectric constant by releasing its moisture or absorbing moisture in the air to cause the first capacitance to change, the humidity sensing unit senses the first capacitance to generate a first capacitance sensing signal. A sensing device, comprising: A humidity sensing unit includes a front surface and a back surface opposite to the front surface, a sensing material is located on the front surface, and a first open back cavity is formed on the back surface so that the sensing material can pass from the first open back cavity A humidity of an environment is sensed. The sensing device of claim 8, wherein: The sensing device further includes a device body, the device body being a semiconductor substrate having a first material portion and a second material portion, and including a carrier; The air pressure sensing unit, coupled to the first material portion, has a cavity and an indication medium reflecting an ambient air pressure; The air pressure sensing unit causes the indicating medium to indicate a value of the ambient air pressure in response to a change in the ambient air pressure; the humidity sensing unit is coupled to the second material portion; The sensing device is a sensing chip with a plurality of sensing units arranged horizontally; The air pressure sensing unit includes the indicating medium, the cavity, and a second electrode layer, the finger The medium is a first electrode layer, and the cavity is disposed between the first electrode layer and the carrier to form a closed space with a fluid, which is outside the closed space and in the first electrode layer Each of the two sides has a groove outside the closed space to reduce the rigidity of the first electrode layer; The humidity sensing unit has a columnar electrode stack forming a plurality of spaced spaces and an interdigitated configuration, and a sensing material disposed in the plurality of spaced spaces, wherein the second material portion of the semiconductor substrate has a first Two open back cavities, and the carrier plate has an opening at the second open back cavity, so as to increase a contact area of the humidity sensing unit; The sensing device further includes a temperature sensing unit, and the semiconductor substrate further has a third material portion; The temperature sensing unit is coupled to the third material portion, the third material portion partially overlaps the first material portion and the second material portion, and the temperature sensing unit includes a P-type semiconductor region and an N-type semiconductor region to form a diode element; The humidity sensing unit and the air pressure sensing unit respectively have a first electrical parameter and a second electrical parameter; The first electrical parameter is a first capacitor, and the second electrical parameter is a second capacitor; the sensing material has a dielectric constant; Under the condition that the sensing material changes the dielectric constant by releasing its moisture or absorbing moisture in the air to cause the first capacitance to change, the humidity sensing unit senses the first capacitance to generate a first capacitance sensing signal; There is a distance between the first electrode layer and the second electrode layer; and Under the condition that the first electrode layer is deformed to change the distance to cause the second capacitance to change, the air pressure sensing unit senses the second capacitance to generate a first capacitance sensing signal. The sensing device of claim 9, wherein: The grooves on both sides of the first electrode layer increase a sensitivity of the air pressure measuring unit; An air pressure sensed by the air pressure sensing unit is proportional to the second capacitance, wherein the air pressure is the ambient air pressure; the ambient air pressure deforms a middle region of the first electrode layer; The second open back cavity reduces the response time of the humidity sensing unit, wherein the carrier has an opening at the second open back cavity; The humidity sensed by the humidity sensing unit is proportional to the first capacitance; The columnar electrode stack layer includes a first columnar electrode layer and a second columnar electrode layer that forms an interdigitated configuration with the first columnar electrode layer, and each electrode layer of the first columnar electrode layer and between each electrode layer of the second columnar electrode layer are electrically connected to each other through a through hole; The sensing material is a polyimide (PI); and There is a thin film between the sensing material and the columnar electrode stack layer to prevent moisture or other corrosive gases from eroding the columnar metal stack layer, wherein the thin film is a Parylene C thin film.

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