KR20210137369A - Humidity sensor and button device including the same - Google Patents

Abstract

Provided is a button device including a humidity sensor. More specifically, the button device includes; a substrate having a plurality of sensing regions; a housing disposed on the substrate and separating a first sensing region of the plurality of sensing regions from other sensing regions; a porous structure within the housing; first and second electrodes disposed on the porous structure and electrically connected to the porous structure; and a temperature sensor disposed adjacent to the first sensing region to sense the temperature of the first sensing region, wherein the porous structure includes a body in which through-holes are formed and an air gap in the body. Accordingly, the measurement sensitivity of the humidity sensor may be improved.

Description

Humidity sensor and button device including the same

The present invention relates to a humidity sensor and a button device including the same, and more particularly, to a humidity sensor including a porous structure and a button device including the same.

The humidity sensor can be divided into an electrical resistance type and a capacitive type. In the electrical resistance method, a material that absorbs water vapor in the air is placed between a pair of electrodes, and the resistance value of the material that varies depending on the degree of absorption of water vapor is measured to calculate the relative humidity. The capacitive method calculates the relative humidity by measuring the dielectric constant of a material that varies depending on the degree of absorption of water vapor. Compared to the capacitive method, the electrical resistance method has a simpler structure and can be mass-produced, but has a disadvantage in that the sensitivity and reactivity at low relative humidity are somewhat inferior.

An object of the present invention is to provide a humidity sensor with improved measurement sensitivity.

Another object to be solved by the present invention is to provide a button device that has high accuracy and can be operated in a non-contact manner.

The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

A button device according to embodiments of the present invention includes a substrate having a plurality of sensing regions; a housing disposed on the substrate and configured to separate a first sensing region among the plurality of sensing regions from other sensing regions; a porous structure in the housings; a first electrode and a second electrode provided on the porous structure and electrically connected to the porous structure; and a temperature sensor disposed adjacent to the first sensing region to sense a temperature of the first sensing region, wherein the porous structure may include a body in which through-holes are formed and an air gap in the body.

In some embodiments, the body may include one of graphene, a transition metal chalcogen compound, and MXene.

In some embodiments, the through-holes may pass through the body in a direction perpendicular to the upper surface of the substrate.

According to embodiments, the maximum width of the through holes may be in a range of 20 nm to 300 nm.

In some embodiments, a bridge may further include a bridge connecting inner walls of the body across the air gap.

In some embodiments, the body may further include a protrusion pattern having a first inner wall and a second inner wall facing each other, and protruding from the first inner wall toward the second inner wall.

A humidity sensor according to embodiments of the present invention includes a substrate; a porous structure provided on the substrate; and a first electrode and a second electrode provided on the porous structure and electrically connected to the porous structure, wherein the porous structure includes a body having through-holes formed therein and an air gap in the body, and the body is It includes a two-dimensional material such as a pin, a transition metal chalcogen compound, and MXene, and the maximum widths of the through holes may be 20 nm or more and 300 nm or less.

In some embodiments, the through-holes may pass through the body in a direction perpendicular to the upper surface of the substrate.

In some embodiments, a bridge may further include a bridge connecting inner walls of the body across the air gap.

According to embodiments, the body has a first inner wall and a second inner wall facing each other,

It may further include a protrusion pattern protruding from the first inner wall toward the second inner wall.

The humidity sensor according to the present invention may include a porous structure. The porous structure may include a plurality of holes to have a high specific surface area. The porous structure may include a two-dimensional material such as graphene, a transition metal chalcogen compound, or MXene. Accordingly, the measurement sensitivity of the humidity sensor may be improved.

As the button device according to the present invention includes a humidity sensor, it is possible to provide a non-contact user interface.

1 is a plan view illustrating a humidity sensor according to embodiments of the present invention.
2 is a perspective view illustrating a humidity sensor according to embodiments of the present invention.
3 is a cross-sectional view taken along line I-I' of FIG. 1 .
4A and 4B are enlarged cross-sectional views for explaining a humidity sensor according to embodiments of the present invention, and correspond to a portion AA of FIG. 3 .
5A and 5B are cross-sectional views for explaining a humidity sensor according to embodiments of the present invention, and correspond to line I-I' of FIG. 1 .
6A and 8A are plan views illustrating a method of manufacturing a humidity sensor according to embodiments of the present invention.
6B and 8B are views for explaining a method of manufacturing a humidity sensor according to embodiments of the present invention, and are cross-sectional views taken along line I to I' of FIGS. 6A and 8A, respectively.
7 and 9 to 11 are views for explaining a method of manufacturing a humidity sensor according to embodiments of the present invention.
12 is a graph showing the sensing sensitivity of the humidity sensor according to embodiments of the present invention.
13 is a perspective view illustrating a button device according to embodiments of the present invention.
14 is a cross-sectional view illustrating a button device according to embodiments of the present invention.

Advantages and features of the present invention, and methods for achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, only this embodiment allows the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout.

The terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. As used herein, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprises' and/or 'comprising' refers to the presence of one or more other components, steps, operations and/or devices mentioned. or addition is not excluded.

Further, the embodiments described herein will be described with reference to cross-sectional and/or plan views, which are ideal illustrative views of the present invention. In the drawings, thicknesses of films and regions are exaggerated for effective description of technical content. Accordingly, the form of the illustrative drawing may be modified due to manufacturing technology and/or tolerance. Accordingly, the embodiments of the present invention are not limited to the specific form shown, but also include changes in the form generated according to the manufacturing process. For example, the etched region shown at a right angle may be rounded or have a predetermined curvature. Accordingly, the regions illustrated in the drawings have a schematic nature, and the shapes of the regions illustrated in the drawings are intended to illustrate specific shapes of regions of the device and not to limit the scope of the invention.

Hereinafter, a humidity sensor according to the concept of the present invention will be described.

1 is a plan view illustrating a humidity sensor according to embodiments of the present invention. 2 is a perspective view illustrating a humidity sensor according to embodiments of the present invention. 3 is a cross-sectional view taken along line I-I' of FIG. 1 .

1 to 3 , the humidity sensor according to an embodiment of the present invention may include a substrate 10 , a first electrode 20 , a second electrode 30 , and a porous structure 40 . .

A substrate 10 may be provided. The substrate 10 may have a flat upper surface 10a. The substrate 10 may be a silicon substrate or a substrate including a polymer. For example, the polymer may be polyethylene terephthalate (PET), polycarbonate (PC), and/or polyethylene naphthalate (PEN). The first direction D1 may be a direction parallel to the upper surface 10a of the substrate 10 . The second direction D2 may be parallel to the upper surface 10a of the substrate 10 , but may be perpendicular to the first direction D1 . The third direction D3 may be a direction perpendicular to the first direction D1 and the second direction D2 .

The porous structure 40 may be provided on the upper surface 10a of the substrate 10 . The porous structure 40 may have a plurality of first through holes HL penetrating the porous structure 40 . In some embodiments, the first through holes HL1 may have a circular shape in a plan view. According to other embodiments, the first through holes HL1 may have an elliptical, quadrangular, triangular, or hexagonal shape in a plan view. The first through holes HL1 may be arranged to be spaced apart from each other in the first direction D1 and the second direction D2 . The first through holes HL1 may pass through the porous structure 40 in the third direction D3 . In some embodiments, the first through hole HL1 may have a constant thickness in the first direction D1 from the upper surface of the substrate 10 to the lower surfaces of the first and second electrodes 20 and 30 . can The first through holes HL1 may improve the specific surface area of the porous structure 40 . Accordingly, the ability to adsorb moisture in the air of the porous structure 40 may be improved.

The maximum width W1 of each of the first through holes HL1 may be in a range of 20 nm to 300 nm. When the maximum width W1 of the first through-holes HL1 is 20 nm or less, the first through-holes HL1 are excessively dense and moisture in the air may not be properly adsorbed. On the other hand, when the maximum width W1 of the first through-holes HL1 is 300 nm or more, water molecules in the air can move smoothly into the first through-holes HL1, but the specific surface area is relatively reduced, so that the sensing sensitivity is decreased. may be lowered.

Specifically, the porous structure 40 may have a body 43 and an air gap AG in the body 43 . The body 43 is a two-dimensional material, and may include one of graphene, a transition metal chalcogenide (TMDC), and MXene. For example, the transition metal chalcogen compound is, for example, molybdenum disulfide (MoS ₂ ), molybdenum diselenide (MoSe ₂ ), molybdenum iteluride (MoTe ₂ ), tungsten disulfide (WS ₂ ), and/or this tungsten selenide (WSe ₂ ), and the like. MXene refers to a transition metal carbide, _{and may include titanium carbide (Ti 3} C ₂ ) and the like. The height of the body 43 (H1, that is, the height of the porous structure 40) may have a range of 10um to 50um.

The air gap AG may be surrounded by the body 43 . That is, the air gap AG may be defined by inner surfaces of the body 43 . 3 , between the plurality of first through holes HL1 , the air gap AG may extend in the third direction D3 . The sidewalls of the body 43 surrounding the air gap AG may have a constant thickness. For example, two sidewalls of the body 43 facing in the first direction D1 with the air gap AG interposed therebetween may have the same thickness in the first direction D1 . For example, an upper wall and a lower wall of the body 43 facing in the third direction D3 with the air gap AG interposed therebetween may have the same thickness in the third direction D3 . The air gap AG may be an empty space after the porous membrane 41 to be described later is removed.

The first electrode 20 and the second electrode 30 may be provided on the porous structure 40 . The first electrode 20 and the second electrode 30 may include, for example, a metal as a conductive material. The metal may include copper (Cu) and/or gold (Au). The first electrode 20 and the second electrode 30 may be any one of an anode and a cathode. For example, when the first electrode 20 is an anode, the second electrode 30 may be a cathode, and when the first electrode 20 is a cathode, the second electrode 30 may be an anode. The first electrode 20 may include a first portion 21 , a second portion 23 , and a plurality of third portions 25 . The first portion 21 of the first electrode 20 may be a portion connected to an external device. For example, the first portion 21 of the first electrode 20 may be a pad portion for connecting the humidity sensor 100 to an external current measuring device. The second portion 23 of the first electrode 20 may be connected to the first portion 21 of the first electrode 20 to extend in the second direction D2 . Each of the third portions 25 of the first electrode 20 extends in the first direction D1 from the second portion 23 of the first electrode 20 and is provided on the upper surface of the porous membrane 41 . can be Each of the third portions 25 of the first electrode 20 may extend toward the second electrode 30 . The third portions 25 of the first electrode 20 may be disposed to be spaced apart from each other in the second direction D2 .

The second electrode 30 may include a first portion 31 , a second portion 33 , and third portions 35 . The first portion 31 of the second electrode 30 may be a portion for connecting an external device and the second electrode 30 . For example, the first portion 31 of the second electrode 30 may be a pad portion connected to an external current measuring device. The second portion 33 of the second electrode 30 may be connected to the first portion 31 of the second electrode 30 to extend in the second direction D2 . Each of the third portions 35 of the second electrode 30 extends from the second portion 33 of the second electrode 30 in the first direction D1 and is provided on the upper surface of the porous membrane 41 . can be Each of the third portions 35 of the second electrode 30 may extend toward the first electrode 20 . The third portions 35 of the second electrode 30 may be disposed to be spaced apart from each other in the second direction D2 . Each of the third portions 35 of the second electrode 30 may be disposed between the third portions 25 of the first electrode 20 . Accordingly, the third portions 35 of the second electrode 30 and the third portions 25 of the first electrode 20 may be alternately disposed in the second direction D2 .

The current input from the external device to the first electrode 20 may pass through the porous structure 40 and be output to the external device again through the second electrode 30 . The body 43 of the porous structure 40 may adsorb water molecules in the air. Accordingly, the resistance value of the porous structure 40 may vary. When the resistance value of the porous structure 40 is changed, the current value between the first electrode 20 and the second electrode 30 is different, so the humidity can be measured by measuring the current value through an external current measuring device. can In the humidity sensor according to an embodiment of the present invention, the porous structure may include a plurality of through holes (H) to increase the specific surface area of the porous structure 40 . Accordingly, the body 43 of the porous structure 40 more effectively adsorbs water molecules in the air over a large area, thereby improving the sensing sensitivity.

4A and 4B are enlarged cross-sectional views for explaining a humidity sensor according to embodiments of the present invention, and correspond to a portion AA of FIG. 3 .

3 and 4A , the porous structure 40 may include a bridge BD. The bridge BD may extend in the first direction D1 to support the body 43 .

Specifically, the body 43 may include a first inner surface 43sa and a second inner surface 43sb facing each other with the air gap AG interposed therebetween. The bridge BD may cross the air gap AG to connect the first inner surface 43sa and the second inner surface 43sb. In some embodiments, the bridge BD may have a narrower thickness as it moves away from the first inner surface 43sa and the second inner surface 43sb. The bridge BD may include a metal oxide. The bridge BD may include, for example, aluminum oxide.

In some embodiments, the body 43 may have two sidewalls facing in the first direction D1 with the air gap AG interposed therebetween. A thickness of each of the two sidewalls in the first direction D1 may be smaller than a width of the air gap AG in the first direction D1 .

3 and 4B , the porous structure 40 may include protrusions PP. The protrusion PP may protrude from the first inner surface 43sa toward the second inner surface 43sb or may protrude from the second inner surface 43sb toward the first inner surface 43sa. The protrusion PP may have, for example, a hemispherical shape. The protrusions PP may include a metal oxide. The protrusions PP may include, for example, aluminum oxide.

5A and 5B are cross-sectional views for explaining a humidity sensor according to embodiments of the present invention, and correspond to line I-I' of FIG. 1 .

Referring to FIG. 5A , the body 43 may have a pipe shape with an upper end 40a closed and an open lower end. Accordingly, the lower end of the air gap AG may be defined by the upper surface of the substrate 10 .

Referring to FIG. 5B , the body 43 may have a pipe shape with an open top and a closed bottom 40b. Accordingly, a portion of the upper end of the air gap AG may be covered by the first electrode 20 and the second electrode 30 .

[Manufacturing method]

6A and 8A are plan views illustrating a method of manufacturing a humidity sensor according to embodiments of the present invention. 6B and 8B are views for explaining a method of manufacturing a humidity sensor according to embodiments of the present invention, and are cross-sectional views taken along line I to I' of FIGS. 6A and 8A, respectively. 7 and 9 to 11 are views for explaining a method of manufacturing a humidity sensor according to embodiments of the present invention.

6A and 6B , a porous membrane 41 may be prepared. The porous membrane 41 may include a metal oxide, for example, aluminum oxide. The porous membrane may be, more specifically, an anodic aluminum oxide (AAO). The porous membrane 41 may have a plurality of second through holes HL2 . The second through-holes HL2 may have a circular shape in a plan view. The maximum width W2 of the second through-holes HL2 may be 50 nm or more and 350 nm or less.

Referring to Figure 7 together with Figures 6a and 6b, the vacuum filtering device (A) can be prepared. The vacuum filtration device (A) may include a vacuum pump (1), a first container (2), a connection part (3), a first solution (SL), and a second container (4). The vacuum pump 1 may be connected to the first container 2 to make the inside of the first container 2 a vacuum condition. A first solution SL may be provided in the second container 4 . The first solution SL may be prepared by dissolving a transition metal chalcogen compound in a solvent. For example, the first solution SL1 may be prepared by dissolving ammonium tetrathiomolybdate ((NH ₄ ) ₂ MoS ₄ ) in a solvent in an amount of 0.5 wt% or more and 5 wt% or less. The solvent may include, for example, ethylene glycol. The first container 2 and the second container 4 may be connected through the connection part 3 . More specifically, a porous membrane 41 may be disposed between the connection part 3 and the second container 4 . The first solution SL in the second container 4 may pass through the porous membrane 41 and fall into the interior of the first container 2 . As a higher level of vacuum condition is formed using the vacuum pump 1 , the first solution SL may permeate the porous membrane 41 well. The first solution SL may conformally coat the surface of the porous membrane 41 while passing through the porous membrane 41 . Specifically, the first solution SL may coat the upper and lower surfaces of the porous membrane 41 and inner surfaces of the second through holes HL2 .

8A and 8B , a heat treatment process may be performed on the porous membrane 41 . The heat treatment process may be performed for 30 minutes or more and 1 hour or less under conditions of 600° C. or more and 1000° C. or less. A heat treatment process may be performed to form a body 43 including _{molybdenum disulfide (MoS 2 ) on the porous membrane 41 .} The body 43 may cover inner walls of the second through holes HL2 and upper and lower surfaces of the porous membrane 41 . The body 43 may cover inner walls of the second through holes HL2 of the porous membrane 41 . Accordingly, the preliminary porous structure 40 ′ may be formed. The preliminary porous structure 40 ′ may have a plurality of first through holes HL1 . The first through-holes HL1 may be substantially the same as those described with reference to FIGS. 1 to 3 .

Referring to FIG. 9 , the second body 50 may be formed on the preliminary porous structure 40 ′. The second body 50 may be formed by providing a PMMA solution on the preliminary porous structure 40 ′ and then performing a spin coating process. The spin coating process may be performed for a time of 10 seconds or more and 30 seconds or less under a rotation condition of 2000 rpm. A poly (methyl methacrylate) (PMMA) solution provided on the preliminary porous structure 40 ′ may conformally cover the surface of the preliminary porous structure 40 ′ through the spin coating process. The second body 50 may expose a portion of the preliminary porous structure 40 ′. For example, a portion of the preliminary porous structure 40 ′ exposed by the second body 50 may be a lower portion of the preliminary porous structure 40 ′. Accordingly, an aqueous sodium hydroxide solution (NaOH) may permeate into the preliminary porous structure 40 ′ in the subsequent etching process. The second body 50 may support the preliminary porous structure 40 ′ while the etching process is performed, thereby preventing the porous structure from being damaged. Accordingly, the preliminary porous structure B in which the second body 50 is formed may be formed.

Referring to FIG. 8 , an etching process may be performed on the preliminary porous structure B provided with the second body 50 . The etching process may be performed using an aqueous sodium hydroxide solution (NaOH). The concentration of the aqueous sodium hydroxide solution (NaOH) may be 0.5M or more and 3M or less. Through the etching process, the porous membrane 41 of the preliminary porous structure 40 ′ may be removed. An air gap AG may be formed in the space in which the porous membrane 41 is removed. Accordingly, the porous structure 40 including the air gap AG and the body 43 may be formed. Since the porous membrane 41 is removed, the flexibility of the porous structure 40 may be improved. The etching process may then include a process of rinsing the porous structure 40 multiple times with distilled water. In the etching process, the second body 50 may not be removed.

Referring to FIG. 9 together with FIG. 3 , the porous structure 40 may be transferred onto the upper surface 10a of the substrate 10 by performing a transfer process. The second body 50 surrounding the porous structure 40 may be removed after the transfer process is performed. 3 , a deposition process may be performed on the upper surface of the porous structure 40 to form the first electrode 20 and the second electrode 30 . According to the manufacturing method, the humidity sensor according to the embodiment described with reference to FIGS. 1 to 3 may be manufactured.

[Experimental Example 1]

Prepare a porous membrane containing anodic aluminum oxide (AAO). (Whatman Laboratory Products) The transition metal chalcogen compound solution is permeated into the porous membrane using a vacuum filtration device. The transition metal chalcogen compound solution is prepared by dissolving ammonium tetrathiomolybdate ((NH ₄ ) ₂ MoS ₄ ) at a concentration of 1.25 wt% using ethylene glycol as a solvent. The porous membrane is heat-treated using a thermochemical vapor deposition (TCVD) method. At this time, the heat treatment temperature is 600 °C or more and 1000 °C or less, and the heat treatment time is 30 minutes or more and 1 hour or less. Accordingly, a porous structure including _{MoS 2 may be formed.} A PMMA solution is coated on the porous structure using a spin coater. At this time, the spin speed is 2000 rpm, and spin coating is performed for 30 seconds. The porous membrane inside the porous structure is removed using an aqueous NaOH solution. After transferring the porous structure onto the prepared substrate, the coated PMMA is removed. A humidity sensor is manufactured by depositing a first electrode and a second electrode on the porous structure. In order to measure the reaction rate according to the humidity change of the humidity sensor, the first reaction time when the relative humidity is increased from 45% to 85% and the second reaction time when the relative humidity is reduced from 85% to 45% measure each.

Table 1 below shows the first reaction time and the second reaction time measured in Experimental Example 1.

first reaction time second reaction time Experimental Example 1 0.47 seconds 0.81 seconds

Referring to Table 1, in the case of [Experimental Example 1], it can be seen that both the first reaction time and the second reaction time showed a reaction time of less than 1 second. It can be seen that the response time of the existing commercially available humidity sensors ranges from several seconds to several tens of seconds, and it can be seen that the response time is fast.

[Comparative Example 1]

A humidity sensor was manufactured under the same conditions as in Experimental Example 1. However, instead of the porous membrane, a film-type membrane that does not include a porous structure is used.

12 is a graph showing the sensing sensitivity of the humidity sensor according to embodiments of the present invention. Equation 1 is an expression showing the definition of the sensor sensitivity of FIG. 12 .

[Equation 1]

Sensor Sensitivity = (I _H /I ₀ )-1

The I _H means a current value measured at the current humidity, and I ₀ means a current value measured at the humidity of the dry air (N ₂ ) in the chamber.

Referring to FIG. 12 together with Equation 1, it can be seen that in the case of Experimental Example 1 (S1), as the relative humidity increases, the slope of the sensor sensitivity sharply increases. On the other hand, in the case of Comparative Example 1 (S2), as the relative humidity increases, it can be seen that the slope of the sensor sensitivity does not change significantly. Accordingly, it can be confirmed that the performance of the humidity sensor is improved by using the porous structure having a high specific surface area in Experimental Example 1.

Hereinafter, a button device including a humidity sensor according to the concept of the present invention will be described.

13 is a perspective view illustrating a button device according to embodiments of the present invention. 14 is a cross-sectional view illustrating a button device according to embodiments of the present invention.

Referring to FIG. 13 , the button device 1000 according to embodiments of the present invention may include a back plate 302 and a plurality of sensor structures SS two-dimensionally arranged on the back plate 302 . can Each of the plurality of sensor structures SS may protrude from the backplate 302 to receive an input signal from a user. According to embodiments, the button device 1000 may be an interface device of an elevator.

The button device 1000 may detect humidity generated by a user's gesture. For example, the user UR may refer to any one of the plurality of sensor structures SS by hand, and the referred sensor structure SS is turned on by sensing the humidity generated in the air from the hand of the user UR. Or it can be turned off. For example, when the button device 1000 is an interface device of an elevator, the button device 1000 may output various signals in response to a user's gesture input. For example, various operation signals may include a signal for lighting of the light emitting element in the sensor structures SS, a signal for generating an acoustic signal from the speaker of the button device 1000, and/or a driving signal for the operation of the elevator. have.

Specifically, referring to FIG. 14 , the button device 1000 may include a substrate 102 having a plurality of sensing regions SR. The substrate 102 may include a control unit and wires connecting the control unit to the plurality of sensor structures SS. The substrate 102 may include, for example, a printed circuit board and a semiconductor chip mounted on the printed circuit board. The plurality of sensing regions SR may be disposed to be spaced apart from each other in a direction parallel to the top surface of the substrate 102 . The plurality of sensing regions SR may have the same size.

Sensor structures SS may be disposed on the sensing regions SR of the substrate 102 . Each of the sensor structures SS may include a humidity sensor 100 , a temperature sensor 200 , and a housing 300 . The housing 300 may be disposed on the substrate 102 to form an internal space in which the humidity sensor 100 and the temperature sensor 200 are provided. The housing 300 may define a sensing region SR. The housing 300 may separate one sensing region SR among the plurality of sensing regions SR from other sensing regions SR.

A humidity sensor 100 may be disposed on the substrate 102 . The humidity sensor 100 may be disposed in the inner space of the housing 300 on the sensing regions SR. The humidity sensor 100 may be the same/similar to the humidity sensor 100 described with reference to FIGS. 1 to 12 . For example, the humidity sensor 100 may include a porous structure 40 and a first electrode 20 and a second electrode 30 electrically connected to the porous structure 40 as shown in FIG. 3 . . The humidity sensor 100 may detect humidity generated by a gesture of the user UR.

A temperature sensor 200 may be disposed on the substrate 102 . The temperature sensor 200 may be disposed in the inner space of the housing 300 on the sensing regions SR. According to embodiments, the temperature sensor 200 may be disposed on one side of the humidity sensor 100 . The temperature sensor 200 may include, for example, a thermocouple or a resistance temperature detector.

The controller may receive a signal including humidity information from the humidity sensor 100 and determine whether the distance d between the user's UR's hand and the sensor structure SS approaches within a threshold distance. For example, the critical distance between the sensor structures SS may have a range of 3 mm to 15 mm. The control unit may include a measurement unit, a signal processing unit, and an operation unit.

The measurement unit may receive a signal including humidity information and temperature information from the humidity sensor 100 and the temperature sensor 200 and provide it to the signal processing unit.

The signal processing unit may include a calibration circuit for calibrating the humidity information before the gesture of the user UR among the temperature information provided from the humidity sensor 100 . The signal processing unit may include a temperature compensation circuit that receives a signal including temperature information and corrects the humidity information according to the temperature of each sensing region SR. The signal processing unit may determine which sensor structure SS the gesture of the user UR points to among the plurality of sensor structures SS by using the humidity change amount information generated by the humidity information and the temperature information. The signal processing unit may provide a sensing signal including information regarding the sensor structure SS pointed to by the user UR to the operation unit.

The operation unit may generate an operation signal by receiving the detection signal from the signal processing unit. The operation signal may include a signal for turning on the light emitting element in the sensor structures SS, a signal for generating an acoustic signal from the speaker of the button device 1000, and/or a signal for driving an elevator.

As described with reference to FIG. 12 , the humidity sensor 100 according to embodiments of the present invention may detect a change in humidity due to a gesture of the user UR within a reaction time of 1 second or less. Therefore, it can be applied to a device that requires an immediate response to a user interface, such as an elevator. As the humidity sensor 100 according to embodiments of the present invention has high sensitivity, it can detect humidity even when separate holes are not formed on the housing 300 . Accordingly, the inflow of foreign substances into the inner space of the housing 300 may be prevented, and thus the stability and reliability of the button device 1000 may be improved.

As described above, embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention may be embodied in other specific forms without changing the technical spirit or essential features thereof. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (10)

a substrate having a plurality of sensing regions;
a housing disposed on the substrate and configured to separate a first sensing region among the plurality of sensing regions from other sensing regions;
a porous structure in the housings;
a first electrode and a second electrode provided on the porous structure and electrically connected to the porous structure; and
and a temperature sensor disposed adjacent to the first sensing region to sense a temperature of the first sensing region,
The porous structure is a button device including a body in which the through-holes are formed and an air gap in the body.
The method of claim 1,
The body is a button device comprising at least one of graphene, a transition metal chalcogen compound, and mexin.
The method of claim 1,
The through-holes pass through the body in a direction perpendicular to the upper surface of the substrate.
The method of claim 1,
A button device having a maximum width of the through-holes in the range of 20 nm to 300 nm.
The method of claim 1,
and a bridge connecting the inner walls of the body across the air gap.
The method of claim 1,
The body has a first inner wall and a second inner wall facing each other,
The button device further comprising a protrusion pattern protruding from the first inner wall toward the second inner wall.
Board;
a porous structure provided on the substrate; and
It is provided on the porous structure, comprising a first electrode and a second electrode electrically connected to the porous structure,
The porous structure includes a body in which through-holes are formed and an air gap in the body,
The body includes a transition metal chalcogen compound,
The maximum widths of the through holes are 20 nm or more and 300 nm or less.
8. The method of claim 7,
The through-holes pass through the body in a direction perpendicular to the upper surface of the substrate.
8. The method of claim 7,
and a bridge connecting the inner walls of the body across the air gap.
8. The method of claim 7,
The body has a first inner wall and a second inner wall facing each other,
The humidity sensor further comprising a protrusion pattern protruding from the first inner wall toward the second inner wall.

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