KR20180060250A - Gas sensor, menufacturing method for the gas sensor and gas sessing device - Google Patents

Abstract

A gas sensor disclosed in an embodiment of the present invention comprises: a semiconductor layer having a plurality of protrusions; a sensing material dispersed on the surface of the protrusion; a first sensor electrode electrically connected with the semiconductor layer; and a second sensor electrode electrically connected with the semiconductor layer, wherein the protrusions are arranged between the first sensor electrode and the second sensor electrode.

Description

TECHNICAL FIELD [0001] The present invention relates to a gas sensor, a gas sensor manufacturing method,

An embodiment relates to a gas sensor.

An embodiment relates to a method of manufacturing a gas sensor.

Embodiments relate to a semiconductor sensor for gas detection and a manufacturing method thereof.

An embodiment relates to a gas sensing device having a gas sensor.

There are many kinds of gases in our living environment. Problems such as gas accidents in general homes, businesses, construction sites, explosion accidents in petroleum combinets, mines, chemical plants, and pollution pollution are continuing. Human sensory organs can not quantitatively determine the concentration of the hazardous gas or can hardly distinguish the type of the gas. In order to cope with this problem, a gas sensor using physical properties or chemical properties of a material has been developed and used for leakage detection, concentration measurement and alarm for gas.

Such gas sensors have been studied for a long time, and many types of gas sensors are now commercially available. When a gas component is adsorbed on the surface of a semiconductor or reacted with an adsorbing gas such as oxygen or the like which has been previously adsorbed, a gas sensor using a semiconductor causes electron exchange between the adsorbing molecules and the surface of the semiconductor, Surface potential, and the like, which are the principle of detecting such a change.

Semiconductor gas sensors are simpler in structure, easier to process, smaller in size and lower in power consumption than optical gas sensors or electrochemical gas sensors through measurement of conductivity by measurement spectrum or ion mobility .

Embodiments provide a gas sensor for gas detection and a method of manufacturing the same.

Embodiments provide a gas sensor having a sensing material that reacts with a gas by light emitted from a semiconductor device and a method of manufacturing the same.

Embodiments provide a gas sensor having a plurality of semiconductor protrusions in which a sensing material reacting with a gas by ultraviolet light is dispersed, and a method of manufacturing the same.

The embodiment provides a gas sensor in which a gas sensing material is dispersed on the surface of protrusions of a conductive semiconductor.

Embodiments provide a gas sensor in which a sensing material that reacts with a gas is disposed on a surface of a plurality of projections projecting from a conductive semiconductor layer.

An embodiment provides a gas sensing device having a gas sensor.

An embodiment provides a gas sensing device having a gas sensor and a semiconductor device in an area adjacent thereto.

An embodiment provides a gas sensor in which a sensing material is dispersed on a surface of a substrate, a conductive type semiconductor layer on the substrate, and protrusions protruding through an insulating layer having a plurality of openings on the conductive type semiconductor layer, and a method of manufacturing the same.

Embodiments provide a sensing sensor for sensing a change in impedance due to a sensing material on a surface of a three-dimensional semiconductor protrusion and a method of manufacturing the same.

A gas sensor according to an embodiment includes: a substrate; A gas sensor disposed on a first region of the substrate; And a semiconductor element disposed on a second region of the substrate, wherein the gas sensor portion includes: a semiconductor layer having a plurality of projections; A sensing member disposed on the projection; And first and second sensor electrodes electrically connected to the semiconductor layer, wherein the semiconductor element includes a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and a second conductivity type semiconductor layer, And an active layer disposed between the conductive semiconductor layers.

A gas sensing device according to an embodiment includes: a circuit board; A gas sensor disposed on a first region of the circuit board; And a semiconductor element disposed on a second region of the circuit board, wherein the gas sensor comprises: a conductive semiconductor layer; An insulating layer having a plurality of first openings on the semiconductor layer; A plurality of protrusions protruding from the semiconductor layer through a first opening of the insulating layer; A sensing material on the surface of the projection; And first and second sensor electrodes electrically connected to the semiconductor layer.

According to an embodiment, the semiconductor light emitting device includes an insulating layer disposed on the semiconductor layer and having an opening in which the plurality of protrusions are disposed, and the protrusion may protrude from the upper surface of the insulating layer.

According to the embodiment, the sensing material may be dispersed on the surface of the protrusions.

According to the embodiment, a part of the projections may include at least one of a polygonal columnar shape, a circular columnar shape, and a pyramidal shape.

According to the embodiment, the semiconductor layer and the first conductivity type semiconductor layer are separated from each other on the substrate, and the semiconductor layer can be disposed between the substrate and the insulating layer.

According to an embodiment, the plurality of protrusions may be disposed between the first sensor electrode and the second sensor electrode, and the first and second sensor electrodes may be disposed on the semiconductor layer.

According to the embodiment, the semiconductor layer may include a semiconductor having an n-type dopant, or may include at least one of group II and group V compound semiconductors and group III and group V compound semiconductors.

According to the embodiment, the protrusion may include the same semiconductor as the semiconductor layer.

According to an embodiment of the present invention, the sensing material includes a main sensing material and a catalyst, and the main sensing material is selected from the group consisting of SnO ₂ , CuO, TiO ₂ , In ₂ O ₃ , ZnO, V ₂ O ₅ , RuO ₂ , WO ₃ , ZrO ₂ , MoO _{3 ,} NiO, CoO, Fe ₂ O ₃ , and AB ₂ O ₄ Wherein the catalyst is selected from the group consisting of platinum (Pt), copper (Cu), rhodium (Rd), gold (Au), palladium (Pd), iron (Fe), titanium (Ti), vanadium V, Cr, Ni, Al, Zr, Nb, Mo, Ru, Rh, Ag, And may include at least one or more of hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), and iridium (Ir).

According to the embodiment, the sensing material may generate electrons by ultraviolet light.

According to an embodiment of the present invention, the sensing material may have an area of 10% or more of the surface area of the protrusions projected through the insulating layer.

According to the embodiment, the projections may have a long length in one direction, or the projections may be connected to each other.

According to an embodiment, the semiconductor device includes a first electrode connected to the first conductivity type semiconductor layer and a second electrode connected to the second conductivity type semiconductor layer, and may emit ultraviolet light.

According to an embodiment of the present invention, the sensing material may be dispersed and arranged in the form of a grain on the surface of the projection.

According to the embodiment, the protrusions are disposed between the first and second sensor electrodes, and are provided with reflection sidewalls around the gas sensor and the semiconductor element, a reflection having a hole for gas inflow on the gas sensor and the semiconductor element, Plate.

A method of manufacturing a gas sensor according to an embodiment includes forming a semiconductor layer having an n-type dopant on a substrate; Forming an insulating layer on the semiconductor layer; Forming a plurality of first openings in the insulating layer; Forming a plurality of protrusions protruding from the semiconductor layer through the first opening; Forming first and second sensor electrodes spaced apart from each other on the semiconductor layer; And dispersing and depositing a sensing material in the form of a grain on the surface of the projection.

The embodiment can improve the reliability of the gas sensor by providing the gas sensor using the light irradiated from the semiconductor element.

The embodiment realizes a gas sensor using light of an LED without a heater, thereby solving the problems of durability of the heater and time required for a warm-up time by the heater.

The embodiment can increase the surface area for sensing the gas sensor by disposing the sensing material on the surface of the projections of the semiconductor material.

Embodiments can improve the sensitivity of the gas sensor.

The embodiment can downsize the gas sensor.

The embodiment can reduce the power consumption of the gas sensor.

Embodiments can improve the reliability of the gas sensor and the gas sensing device having the gas sensor.

1 is a plan view of a gas sensor according to a first embodiment.
2 is a cross-sectional view of the gas sensor of Fig. 1 on the AA side.
FIG. 3 is a view showing protrusions and sensing members in the gas sensor of FIG. 2. FIG.
4 (A) to 4 (D) show a modification of the plan view of the projection.
5 is a modification of the projection of the gas sensor of Fig.
FIG. 6 is a view showing another arrangement of projections in the gas sensor of FIG. 1;
7 is a view showing another arrangement of protrusions in the gas sensor of FIG.
8 is a view showing another arrangement of protrusions in the gas sensor of FIG.
9 is a plan view of the gas sensor according to the second embodiment.
10 is a plan view showing a modification of the gas sensor of FIG.
11 is a view showing a modified example of the gas sensor of Fig.
12 is a perspective view showing a gas sensor according to the third embodiment.
13 is a diagram showing an example of a light emitting element in the gas sensor of Fig.
14 is a perspective view showing a gas sensor having a reflection plate as a modification of the third embodiment.
15 is a plan view of a gas sensor as a modification of the third embodiment.
16 is a side cross-sectional view of the gas sensor according to the fourth embodiment.
17 is a block diagram of a gas sensing system having a gas sensor according to an embodiment.
18 to 21 are views showing a method of manufacturing a gas sensor according to an embodiment.
22 is a view showing current flow in accordance with ultraviolet light in the projections and sensing members according to the embodiment.
23 is a view showing a current distribution according to the width of the projection of the gas sensor according to the embodiment.
24 is a graph comparing gas sensing sensitivity according to the size of the sensing material according to the embodiment.
25 is a graph showing the sensitivity of the gas sensing sensor according to the embodiment according to sensing.

The embodiments may be modified in other forms or various embodiments may be combined with each other, and the scope of the present invention is not limited to each embodiment described below. Although not described in the context of another embodiment, unless otherwise described or contradicted by the description in another embodiment, the description in relation to another embodiment may be understood. For example, if the features of configuration A are described in a particular embodiment, and the features of configuration B are described in another embodiment, even if the embodiment in which configuration A and configuration B are combined is not explicitly described, It is to be understood that they fall within the scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. In the description of the embodiment according to the present invention, in the case of being described as being formed "on or under" of each element, the upper (upper) or lower (lower) or under are all such that two elements are in direct contact with each other or one or more other elements are indirectly formed between the two elements. Also, when expressed as "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

<Examples>

FIG. 1 is a plan view of the gas sensor according to the first embodiment, FIG. 2 is a cross-sectional view of the gas sensor taken along line A-A of FIG. 1, and FIG. 3 is a view showing protrusions and sensing members in the gas sensor of FIG.

1 to 3, the gas sensor 10 includes a semiconductor layer 21, a plurality of projections 23 on the semiconductor layer 21, and a plurality of projections 23 on the plurality of projections 23 ). The gas sensor 10 includes a plurality of sensor electrodes 41 and 43 connected to the semiconductor layer 21. The gas sensor 10 includes a base side substrate 11 and the semiconductor layer 21 may be disposed on the substrate 11. [ An insulating layer 31 may be disposed on the semiconductor layer 21.

&Lt; Substrate (11) >

1 and 2, the substrate 11 may be a conductive or insulating material. The substrate 11 may be a semiconductor substrate or a non-semiconductor substrate. The substrate 11 may be a light-transmitting or non-light-transmitting substrate. The substrate 11 may be selected from the group consisting of a sapphire substrate (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ and GaAs. The substrate 11 may be formed of a GaN-based semiconductor, for example, a GaN semiconductor. The substrate 11 may be a bulk GaN single crystal substrate. The substrate 11 may be used as a support member for supporting the gas sensor 10. [

The thickness of the substrate 11 may be in the range of 30 탆 or more, for example, 30 탆 to 300 탆. When the thickness of the substrate 11 is smaller than the thickness of the above range, Can be large. The length of the substrate 11 in the direction of the first axis X and the length of the direction of the second axis Y may be the same or different. For example, the length of the substrate 11 in the X-axis direction may be greater than the length in the Y-axis direction. The gas sensor 10 may be provided with the substrate 11 removed or without a substrate.

<Semiconductor Layer 21>

As shown in FIGS. 1 and 2, the semiconductor layer 21 may include a conductive semiconductor. The conductive semiconductor layer 21 may be an n-type semiconductor layer having an n-type dopant or a p-type semiconductor layer having a p-type dopant. The embodiment will be described as an example of the n-type semiconductor layer. The dopant concentration added to the semiconductor layer 21 may be 5E16 or more, for example, 5E17 or more. The n-type dopant may include a dopant such as Si, Ge, Sn, Se, and Te.

The semiconductor layer 21 may be disposed as a compound semiconductor of group II to VI elements. The semiconductor layer 21 may include at least one of group II and group V compound semiconductors and group III and group V compound semiconductors. The semiconductor layer 21 may be formed of at least one of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, and ZnO. The semiconductor layer 21 may include a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + y? The semiconductor layer 21 may include a GaN-based semiconductor. The semiconductor layer 21 may be a single layer or a multilayer, and may include a different semiconductor layer in the case of the multi-layer. At least one of the multi-layered semiconductor layers, for example, the sensor electrodes 41 and 43, may be contacted.

A buffer layer (not shown) may be disposed between the semiconductor layer 21 and the substrate 11. The buffer layer may be disposed of a compound semiconductor of group II to VI elements. The buffer layer may include at least one of group II and group V compound semiconductors and group III and group V compound semiconductors. The buffer layer may be formed of at least one of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP and ZnO. The semiconductor layer 21 may include a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + y? The buffer layer may be a doped semiconductor or an unintentional doped semiconductor.

<Projections (23)>

1 to 3, the protrusions 23 may be electrically connected to the semiconductor layer 21. The protrusions 23 may be made of a semiconductor material. The protrusion 23 may include the same material as the semiconductor layer 21. The protrusion 23 may include a conductive semiconductor, for example, an n-type semiconductor or a p-type semiconductor. The protrusions 23 may be arranged as compound semiconductors of group II to VI elements. The projections 23 may include at least one of group II and group V compound semiconductors and group III and group V compound semiconductors. The protrusions 23 may be formed of at least one of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, and ZnO. The projections 23 may include a composition formula of In _x Al _y Ga _1-xy N (0? X? 1, 0? _Y? 1, 0? _X + y? The protrusion 23 may include a GaN-based semiconductor. The protrusions 23 may be a single layer or a multi-layer, and may include different semiconductor layers in the case of the multi-layer. The dopant concentration added to the protrusion 23, for example, the n-type dopant concentration may be 5E16 or more, for example, 5E17 or more. The protrusion 23 may be a conductive type material.

The projections 23 may protrude from the semiconductor layer 21. A plurality of the protrusions 23 may be arranged at regular intervals D1 or may be arranged at different intervals, but the invention is not limited thereto. The protrusions 23 may be arranged in a plurality of rows R1 and a plurality of protrusions 23 may be arranged in each row R1 with a predetermined period D3. The period D3 is a distance in the Y-axis direction, and may be the same as or different from the period D1 in the X-axis direction.

The protrusions 23 may be in the form of a rod, for example, a polygonal column, a columnar columnar shape, or a pyramidal shape. The protrusion 23 may have a hexagonal column, octagonal column or triangular column shape as shown in FIG. 4 (A) - (C), or may have a columnar shape as shown in FIG. 4 (D). The upper portion of the protrusion 23 may be formed in a pyramid shape or a flat horizontal surface. When the projections 23 and the upper portion thereof have a polygonal shape, the surface area can be increased. As another example, the projections 23 may be at least partially horn-shaped or truncated. The protrusions 23 may be arranged in a matrix form. The surface area of the protrusions 23 can be increased and the surface area of the protrusions 23 can be increased so that the impedance due to the sensing material 51 disposed on the surface of the protrusions 23 can be increased or decreased.

2, the width D2 of the protrusion 23 may be a nanometer size or more. The width D2 of the protrusion 23 may be in a range of 100 nm or more, for example, 100 nm to 2000 nm. When the width D2 of the protrusion 23 is less than 100 nm, the surface area is reduced and the area occupied by the sensing material 51 is reduced or the protrusion 23 is difficult to form. If the width D2 of the protrusion 23 exceeds 2000 nm, the sensor sensitivity of the gas may be deteriorated. As shown in FIG. 23, the width D2 of the protrusion 23 shows that the photocurrent increases at a diameter of 100 nm or more. The height H1 of the protrusion 23 may be greater than the thickness T1 of the insulating layer 31. [ The height H1 of the protrusion 23 may range from 250 nm to 2000 nm. If the protrusion 23 is smaller than the above range, the surface area of the protrusion 23 is small and the sensing area can be reduced. ) May be damaged.

As another example of the protrusion 23, a material such as a nano powder, a nano wire, a carbon nanotube (CNT), and a graphene may be used. As another example, instead of the semiconductor layer 21, a conductive layer made of a metal or a non-metal material may be disposed between the substrate 11 and the insulating layer 31. The protrusions 23 may be formed of a semiconductor material or a metal or a non-metal material.

<Insulating layer 31>

As shown in FIGS. 1 and 2, the insulating layer 31 may be disposed on the semiconductor layer 21. The insulating layer 31 may be formed of a nitride or an oxide based insulating material and may be formed of a material such as SiNx (X> 0), SiO ₂ , SiO _x (X> 0), SiO _x N _y ), Si ₃ N ₄ , and Al ₂ O ₃ . When the insulating layer 31 is made of SiN, the semiconductor layer 21 may be formed using the same equipment. As another example, the insulating layer 31 may be formed as a single layer or a multilayer. The insulating layer 31 may be an unintentionally doped semiconductor or a non-polar type semiconductor doped with an n-type dopant and a p-type dopant. The thickness T1 of the insulating layer 31 may be less than the thickness of the substrate 11. The thickness (T1) of the insulating layer 31 may be thinner or thicker than the thickness of the semiconductor layer 21. The thickness T1 of the insulating layer 31 may be in a range of 200 nm or more, for example, 500 nm to 10000 nm. If the thickness T1 of the insulating layer 31 is less than the above range, electrical interference may occur. If the thickness T1 exceeds the above range, the surface area of the projections 23 may decrease or the size of the gas sensor 10 may increase .

The sensing material 51 may also be attached to the upper surface of the insulating layer 31. The insulating layer 31 may have a first opening 33 in a region corresponding to a lower portion of the protrusion 23. The width B1 of the first opening 33 may be equal to or less than the width D2 of the projection 23. [ That is, the protrusions 23 are arranged at a width D2 that is equal to or greater than the width B1 of the first openings 33, overlapping the first openings 33 in the Z-axis direction, 31 in the Z-axis direction. The first opening 33 may have a circular top view or a polygonal top view. The first opening 33 may be a hole through which the insulating layer 31 penetrates in a vertical direction and may be a region in which the semiconductor layer 21 is exposed. The first openings 33 may be arranged in the same number as the number of the projections 23.

The insulating layer 31 may include second and third openings 35 and 37. The first sensor electrode 41 may be disposed in the second opening 35 and the second sensor electrode 43 may be disposed in the third opening 37. The second and third openings 35 and 37 may be disposed on opposite sides of the first openings 33. The size of the second and third openings 35 and 37 may be greater than the size of the first opening 33. The insulating layer 31 may be removed on the gas sensor 10. This removal process of the insulating layer 31 can be removed after the sensing reformation.

&Lt; Sensing material (51) >

The sensing material 51 may be disposed on the surface of the protrusion 23. The sensing material 51 may be disposed on the surface of the protrusion 23 and on the upper surface of the insulating layer 31. The sensing material 51 may be formed of a metal oxide material. The sensing material 51 may include a main sensing material and a catalyst. The main sensing material comprises a metal oxide material, and the catalyst may comprise a metal. The main sensing material may be selected from the group consisting of SnO ₂ , CuO, TiO ₂ , In ₂ O ₃ , ZnO, V ₂ O ₅ , RuO ₂ , WO ₃ , ZrO ₂ , MoO _{3 ,} NiO, CoO, Fe ₂ O ₃ , ₂ O ₄ , &Lt; / RTI &gt; and the like. The catalyst of the sensing material 51 may be at least one selected from the group consisting of Pt, Cu, Rh, Au, Pd, Fe, Ti, (Cr), nickel (Ni), aluminum (Al), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium Hf), tantalum (Ta), tungsten (W), rhenium (Re), iridium (Ir) Such a catalyst material may be mixed with the main sensing material as a doping material in the sensing material 51. [ The sensing material 51 may comprise materials that may have both sensing and catalytic properties. The material of the sensing material 51 according to the embodiment may be selectively mixed with the main sensing material and the catalyst depending on the kind of gas to be sensed.

The sensing material 51 may be provided in a grain shape, and the sizes of the sensing materials 51 may be the same or different from each other. The size of the grain may be in the range of 2 nm or more, for example, in the range of 2 nm to 20 nm. If the grain size is smaller than the above range, the grain size of the grain 51 may be insignificant. . The sensing material 51 may be attached to the surface of the protrusions 23 to change the impedance. Here, as shown in FIG. 24, it can be seen that as the concentration of carbon dioxide increases, the sensing response of the sensing material is further increased at a smaller grain size (e.g., microwave assisted).

The sensing material 51 can mix one or two or more kinds of main sensing materials, and the mixed material can be doped with one or two kinds of catalyst materials. The catalyst material may be added in an amount of 5 wt% or less, for example, 1 wt% to 5 wt% of the main sensing material, and the gas sensing sensitivity may be lowered when the catalyst material exceeds the above range. For example, when the SnO ₂ and ZnO are mixed with each other, the sensing material 51 may mix SnO ₂ in a larger proportion than ZnO, for example, the molar ratio of SnO ₂ : ZnO may range from 1.1: 1 to 2.5: 1 , And the catalyst material can be doped with, for example, platinum (Pt) in the range of 1 wt% to 3 wt% of the main sensing material.

Electrons are generated when the light L1 generated from the semiconductor element is irradiated to the gas sensor 10 according to the embodiment and the sensing material 51 is first reacted with nitrogen or oxygen which occupies the largest composition ratio in the atmosphere Can happen. The nitrogen does not react with the sensing material 51 in the gas sensor 10 as an inert gas and oxygen is adsorbed on the surface of the sensing material 51 to form oxide ions such as O ^2- , O ₂ ^- and O ^- In this case, the oxide ions and the gas react with each other to move the electrons. At this time, a very large change in impedance, that is, a high sensitivity characteristic, may be caused by the electron movement on the surface of the projection 23. [ That is, the sensing material 51 generates oxidized ions by reaction of electrons generated in response to the light L1 and oxygen, and the oxidized ions react with the gas to move electrons through the sensing material 51 . The movement of electrons in the sensing material 51 can change the impedance and the impedance change of the sensing material 51 can be detected by the sensor electrodes 41 and 43. The impedance of the sensing material 51, which senses the gas, may be higher or lower than the impedance of the semiconductor layer 21. The gas may include H ₂ , CO ₂ , CO, HCl, Cl ₂ , H ₂ S, H ₂ , HCN, and the like. The sensing material 51 may be a semiconductor ceramic material and may have an impedance value in the range of several hundreds of k [Omega] to several tens of M [Omega] through process and heat treatment.

&Lt; Sensor electrodes (41, 43) >

The sensor electrodes 41 and 43 may be disposed on the semiconductor layer 21. The sensor electrodes 41 and 43 include a first sensor electrode 41 and a second sensor electrode 43 which are electrically connected to each other on the semiconductor layer 21 and are spaced apart from each other.

The first and second sensor electrodes 41 and 43 may be located on opposite sides of the region where the protrusions 23 are disposed. At least one or more of the protrusions 23 may be disposed in a region between the first and second sensor electrodes 41 and 43.

The sensor electrodes 41 and 43 may be formed of a metal material such as Au, Pt, Al, Ag, Ti, TiN, Layer or multi-layer using at least one of tungsten (W), ruthenium (Ru), iridium (Ir), and copper (Cu), an alloy or a different material. The sensor electrodes 41 and 43 may include a laminate structure of an adhesive layer and a bonding layer, and may be formed of a Ti / Au layer structure or a Cr / Au structure. The sensor electrodes 41 and 43 may have a thickness of 200 nm or more, for example, 300 nm or more.

The length C1 in the X-axis direction of each of the sensor electrodes 41 and 43 may be smaller than the interval C3 between the sensor electrodes 41 and 43. [ The length C2 of the sensor electrodes 41 and 43 in the Y-axis direction may be equal to or different from the length of the region in which the protrusions 23 are arranged in the Y-axis direction. The first and second sensor electrodes 41 and 43 are electrically connected to the semiconductor layer 21 and can detect a change in impedance due to the sensing material 51 attached to the surface of the protrusions 23. The presence or absence of gas leakage can be sensed through the impedance change caused by the first and second sensor electrodes 41 and 43.

The first and second sensor electrodes 41 and 43 may be connected to a lead pattern in a circuit board or a package through a wire, or may be die-bonded. As another example, although the first and second sensor electrodes 41 and 43 are disposed on the semiconductor layer 21, the first and second sensor electrodes 41 and 43 may be disposed on the lower surface of the semiconductor layer 21, ). &Lt; / RTI &gt; As another example, when the substrate 11 is made of a conductive material, the first and second sensor electrodes 41 and 43 may be disposed under the substrate 11.

The sensing material 51 according to the embodiment may be irradiated with light emitted from a semiconductor element, for example, a light emitting diode (LED). When the light emitted from the LED is irradiated, the sensing material 51 generates electrons. The generated electrons react with the surrounding oxygen to generate oxide ions such as O ^2- , O ₂ ^- and O ^- The oxide ions can move electrons when they react with the gas. The impedance of the sensing material 51 changes with the movement of the electrons. The change in the impedance is caused by a change in impedance between the first and second sensor electrodes 41 and 43 connected to the semiconductor layer 21. The change in impedance is caused by the signal detection connected to the first and second sensor electrodes 41 and 43 Gas detection can be detected by the circuit. 25, when the ultraviolet light is irradiated to the sensing material and the external nitrogen dioxide (NO ₂ ) flows in, the level of the sensing sensitivity changes according to the resistance change of the sensing material. Accordingly, have. At this time, the level of the sensing sensitivity may be a low level when the UV light is off, and may be a high level when the UV light is on.

The LED may include at least one of ultraviolet light, visible light, and infrared light. The LED may comprise ultraviolet light. The sensing material 51 generates electrons on the surface of the sensing material when the ultraviolet light L1 is irradiated. The ultraviolet wavelength may have a wavelength of 390 nm or less, for example, 200 nm to 390 nm. The wavelength of the ultraviolet light may be different depending on the band gap of the main sensing material. For example, in the case of SnO ₂ , the band gap may be about 3.6 eV. As shown in FIG. 22, when ultraviolet (UV) light is irradiated on the sensing material, it is understood that a current flows when the sensing material is, for example, 254 nm or 365 nm. The embodiment can improve the reliability of the gas sensor 10 by providing the gas sensor 10 that generates electrons using the light of the LED. The embodiment realizes the gas sensor 10 using the light of the LED without the heater, thereby solving the problems of the durability of the heater and the warm-up time of the heater.

The surface of the protrusions 23 can be increased by protruding protrusions 23 made of a semiconductor material in a column shape and contacting and dispersing the sensing material 51 on the surface of the protrusions 23. Accordingly, the gas sensing sensitivity of the gas sensor 10 can be improved. The embodiment can downsize the gas sensor 10. The embodiment does not drive a separate heater, so the power consumption of the gas sensor 10 can be reduced.

The protrusions 23 can be aligned through the first openings 33 of the insulating layer 31 so that the number and height of the protrusions 23 can be adjusted. The surface area or the number of the projections 23 can be efficiently controlled.

The semiconductor layer 21 and the protrusions 23 are formed of a semiconductor material so that a photo current flows when the semiconductor material is irradiated with ultraviolet light, So that the impedance of the antenna is changed. The first and second sensor electrodes 41 and 43 are connected to each other by using the impedance change in the protrusion 23 by the ultraviolet light and the impedance change of the sensing material 51 dispersed on the surface of the protrusions 23. [ The gas sensing state can be detected.

2, the distance D4 between the protrusions 23 may be greater than the width D2 of the protrusions 23. As shown in FIG. For example, the distance D4 between the projections 23 may be in the range of 1 占 퐉 or more, for example, 1 占 퐉 to 3 占 퐉. If the distance between the protrusions 23 is larger than the above range, the impedance applied to the first and second sensor electrodes 41 and 43 may be increased. If the distance is smaller than the above range, Interference may occur.

The sensing member 51 may have a surface area of 10% or more, for example, 10% to 80% of the surface area of the protrusions 23 when the surface area of the protrusions 23 exposed on the insulating layer 31 is 100% % &Lt; / RTI &gt; It is difficult to control the distribution area of the sensing material 51 when the sensing material 51 is smaller than the above range and can be formed as a sensing material 51 in the form of a film when the sensing material 51 is larger than the above range, the sensitivity may be lowered.

1 and 2, protrusions 23 between the first and second sensor electrodes 41 and 43 may be M rows × N columns or more (M ≧ 1, N ≧ 1). The first sensor electrode 41 may be separated from the protrusion 23 by a first gap G1 and the first gap G1 may be larger than a gap D4 between the protrusions 23. [ The first gap G1 may be in the range of 5 占 퐉 or more, for example, 5 占 퐉 to 15 占 퐉. If the first gap G1 is smaller than the above range, it may be difficult to form the second opening 35 because it is adjacent to the protrusions 23. If it is larger than the above range, the size of the gas sensor may be increased have. The second gap G2 between the second sensor electrode 43 and the adjacent protrusion 23 may be equal to or different from the first gap G1 and is not limited thereto.

In the embodiment, the interval C3 between the first and second sensor electrodes 41 and 43 may be 50 탆 or more. The distance C3 between the first and second sensor electrodes 41 and 43 may be in the range of 100 m to 200 m. If the distance C3 between the first and second sensor electrodes 41 and 43 is smaller than the above range, the interval between the projections 23 may be narrowed or the number of the projections 23 may be reduced, If it is larger than the above range, the impedance can be increased.

The upper portion of the projection 23 according to the embodiment may have a polygonal pyramid shape. Since the upper portion of the protrusion 23 has a polygonal cone structure, the surface area of the protrusion 23 can be increased.

As shown in Fig. 4A, the projection 23 has a hexagonal prismatic side surface S1 and a flat upper surface S2. Alternatively, as shown in Fig. 4B, And can have a flat upper surface S2 having side surfaces S1 of each columnar shape. This is because the projections may be deformed into a quadrangular to hexagonal columnar shape, and the upper portion thereof may be a flat surface or a horn structure. As shown in FIG. 4C, the protrusion 23 may have a triangular structure, and the upper portion may be a flat upper surface S2 or a conical structure. As shown in FIG. 4D, And the upper portion thereof may have a flat upper surface S2 or may have a horn shape.

5 is a modification of the protrusion of Fig. 5, the insulating layer 31 is disposed on the semiconductor layer 21 and the protrusions 23 protrude through the first opening 33 of the insulating layer 31. [ The protrusion 23 includes a lower portion 23A having the same shape as the first opening portion 33 of the insulating layer 31 and an upper portion 23B protruding higher than the upper surface of the insulating layer 31. The bottom of the upper portion 23B of the protrusion 23 may be disposed on a part of the upper surface of the insulating layer 31 disposed around the first opening 33. [ The lower portion 23A of the protrusion 23 may have the same width as the width B1 of the first opening 33. [ The lower portion 23A of the protrusion 23 may have the same shape as that of the first opening 33. The upper portion 23B of the projection 23 may have a polygonal pyramid shape, for example, a hexagonal pyramid shape. The bottom of the upper portion 23B may have a width D1 greater than the width B1 of the first opening 33 when the upper portion 23B of the projection 23 is polygonal. The upper surface 23B of the projection 23 is disposed on the upper surface of the insulating layer 31 disposed around the first opening 33 on the first opening 33 so that the surface area of the projection 23 Can be increased. The sensing material 51 may be dispersed and disposed on the surface area of the projections 23. The first and second sensor electrodes 41 and 43 may be electrically connected to the semiconductor layer 21 and the impedance of the sensing material 51 may be changed by the light of the LED, Can be detected.

The semiconductor layer 21, the protrusion 23, the sensing material 51, and the first and second sensor electrodes 41 and 43 will be described with reference to the structures of the above embodiments. The outer shape of the lower portion 23A of the projection 23 and the outer shape of the upper portion 23B may have different shapes.

Fig. 6 is a view showing another arrangement of the projections 23 in the gas sensor 10 of Fig. Referring to Fig. 6, the projections 23 may differ in the number of the projections 23 of the two adjacent rows R1 and R2 when viewed from the top view. The projections 23 of the adjacent rows R1 and R2 may be arranged in a jig jig shape. In this case, the number of rows of protrusions 23 corresponding to the directions of the first and second sensor electrodes 41 and 43 is increased.

7 is a view showing another arrangement of the projections 23 in the gas sensor 10 of Fig.

Referring to FIG. 7, the protrusions 23 may have different shapes of the protrusions 23 and 23C of the two adjacent rows R1 and R2 when viewed from the top view. For example, the projections 23 of one row R1 may have a hexagonal columnar shape, and the projections 23C of the other row R2 may have a triangular columnar shape. The protrusions 23 and 23C of the adjacent rows R1 and R2 may have different shapes and arranged in a jig. As another example, the projections of the other row R2 may be circular columns, but are not limited thereto. The protrusions 23 and 23C may be changed according to the shape of the first opening, but are not limited thereto.

Referring to FIG. 8, the sensor electrodes 41 and 43 may include branch electrodes 41A and 43A. The first sensor electrode 41 is disposed adjacent to the first and third sides S1 and S3 of the insulating layer 31 and the second sensor electrode 43 is disposed adjacent to the second and third sides of the insulating layer 31. [ Four side surfaces S2, S4. The first and second side surfaces S1 and S2 may be opposite to each other and the third and fourth side surfaces S3 and S4 may be opposite to each other and perpendicular to the first and second side surfaces S1 and S2.

The first branched electrode 41A has at least one first branch electrode 41A extending in the Y-axis direction toward the second side S2 of the insulating layer 31, . The first branched electrode 41A may be disposed on the semiconductor layer 21 of FIG. 2 and may be electrically connected to the semiconductor layer 21. The first branched electrode 41A may extend with a width C4 smaller than the length C2 in the X axis direction of the first sensor electrode 41. [ The length C5 of the first branched electrodes 41A in the Y-axis direction may be greater than the period D3 of the protrusions 23 in the Y-axis direction. At least two protrusions 23 may be disposed in a region corresponding to the first branch electrode 41A. The first branched electrode 41A may be disposed adjacent to the protrusions 23 and may correspond to the second sensor electrode 43. [

The second branched electrode 43A may have at least one second branched electrode 43A and the second branched electrode 43A may be connected to the first side S1 of the insulating layer 31 in a direction Y And can extend in the axial direction. The second branched electrode 43A may be disposed on the semiconductor layer 21 of FIG. 2 and may be electrically connected to the semiconductor layer 21. The second branch electrode 43A may extend with a width (e.g., C6) smaller than the length of the second sensor electrode 43 in the X-axis direction. The length C7 of the second branched electrodes 43A in the Y-axis direction may be greater than the period D3 of the protrusions 23 in the Y-axis direction. At least two protrusions 23 may be disposed in a region corresponding to the second branched electrode 43A. The second branched electrode 43A may be disposed adjacent to the protrusions 23 and may correspond to the first sensor electrode 41. [ The protrusions 23 may be divided into a center area A1 and an area A2 adjacent to the first branched electrode 41A and an area A3 adjacent to the second branched electrode 43A. May be disposed between the first and second sensor electrodes 41 and 43.

Portions of the first and second sensor electrodes 41 and 43 may overlap in the X-axis direction. The branch electrodes 41A and 43A may be disposed on the first and second sensor electrodes 41 and 43 and the protrusions 23 may be further disposed on a region adjacent to the branch electrodes 41A and 43A. On the surface of the protrusions 23, a sensing material 51 is dispersed and disposed to generate electrons by reacting with light emitted from the LED, for example, ultraviolet rays, and the generated electrons and peripheral oxygen react with each other to generate oxide ions The oxidizing ions and the gas react with each other to move the electrons, thereby detecting the change in the impedance of the sensing material 51.

9 is a plan view of the gas sensor according to the second embodiment. In describing the second embodiment, the same configuration as that of the first embodiment refers to the configuration of the first embodiment, and the configuration of the first embodiment can be selectively used.

9, the gas sensor has a plurality of protrusions 25 protruding from the semiconductor layer 21 on the insulating layer 31. The protrusions 25 protrude from the first and second sensor electrodes 41 and 43, As shown in FIG. The plurality of projections 25 may have a length D5 in the X-axis direction that is at least two times longer than a length D2 in the Y-axis direction. The protrusions 25 may have a stripe shape in any one of the X and Y axis directions, for example, the X axis direction.

The plurality of projections 25 may be arranged in two or more rows in the Y-axis direction. The length D5 of each protrusion 25 may be 30% or more, for example, 50% or more of the interval C3 between the first and second sensor electrodes 41 and 43. The length D2 of the protrusions 25 in the Y-axis direction may be in the range of 100 nm or more, for example, 100 nm to 2000 nm, as the width of the protrusions 23 described above. The sensing member 51 disclosed in the embodiment can be dispersedly disposed on the surface of the projection 25. [ The protrusions 25 may be provided with a long length in either one axial direction so that they have a larger surface area than the surface area of the protrusions 25 in Fig. The first and second sensor electrodes 41 and 43 can detect a change in impedance of the sensing material 51 that is irradiated with light from the LED and reacts with external gas.

Fig. 10 is a modification of Fig. 9, and may have at least one or both of a plurality of recesses 26A and protrusions on the surface of the protrusion 26. Fig. At least one or both of the plurality of recesses 26A and protrusions can increase the surface area of the protrusions 26. [ The recess 26A is concave in the Y-axis direction toward the inner side of the projection 26 and can be spaced apart by a predetermined distance in a shape of a long depression in the vertical direction, for example, the Z-axis direction. Each of the recesses 26A may have a polygonal or hemispherical cross-section. The protrusions may protrude in the Y-axis direction toward the outer side of the protrusions 26 and have a long length in the Z-axis direction. Each of the projections may have a polygonal or hemispherical cross-section. The sensing material 51 may be dispersedly disposed on the surface of the protrusion 26 and on the surface of the recess 26A and / or the protrusion. Accordingly, the surface area of the entire projections 23 can be increased, and the sensitivity of detection by the sensing material 51 can be increased.

11 is a view showing a modified example of the gas sensor of Fig.

Referring to FIG. 11, the projections 27 are arranged with a length D6 which is long in one direction, for example, in the Y-axis direction, and the projections 27 can be connected to each other in a predetermined region. The length D6 of the projection 27 in the Y-axis direction may be 30% or more, for example, 50% or more of the length C2 in the Y-axis direction of the first and second sensor electrodes 41 and 43 . Adjacent projections 27 may be connected to each other by connecting portions 27B and 27C. Since the connection portions 27B and 27C connect the two adjacent projections 27, the structure of the projections 27 can be provided in a continuously connected line shape. The connection portions 27B and 27C of the projections 27 can be connected to each other at the upper and lower ends of two adjacent projections 27 continuously. The projection 27 may be provided with a recess 27A and / or a projection, and the recess 27A and / or the projection may be arranged in a vertically long groove or protruding shape.

12 is a perspective view showing a gas sensor or a gas sensing device according to the third embodiment. In describing the third embodiment, the same parts as those of the embodiment (s) disclosed above can be selectively used.

Referring to FIG. 12, a gas sensor or gas sensing device may include a gas sensor portion 10A and a semiconductor device 101 adjacent thereto. The semiconductor device 101 may be integrally formed or separated from the gas sensor portion 10A on the substrate 11. [ In this case, the semiconductor device 101 may include the gas sensor unit 10A, or the gas sensor unit 10A may include the semiconductor device 101. The gas sensor portion 10A may optionally include the gas sensor disclosed in the embodiment (s) of Figs. 1-11, and will be described with reference to the description disclosed in the above embodiment. For example, the gas sensor unit 10A includes a semiconductor layer 21, a plurality of protrusions 23 on the semiconductor layer 21, and a sensing material 51 on the plurality of protrusions 23. The gas sensor unit 10A includes first and second sensor electrodes 41 and 43 connected to the semiconductor layer 21. The gas sensor portion 10A includes a base side substrate 11 and the semiconductor layer 21 may be disposed on the substrate 11. [ An insulating layer 31 may be disposed on the semiconductor layer 21.

The gas sensor may include a gas sensor portion 10A disposed on a first region of the substrate 11 and a semiconductor device 101 disposed on a second region of the substrate 11. [ The first and second regions may be different regions on the upper surface of the substrate 11. The first area where the gas sensor part 10A is disposed may be smaller than the area of the second area where the semiconductor device 101 is disposed. Here, the semiconductor device 101 may include the substrate 11 or may be integrally disposed or separated on the substrate of the gas sensor unit 10A. The gas sensor portion 10A may be disposed adjacent to or corresponding to at least one side of the side surfaces of the semiconductor device 101. [

The semiconductor device 101 may emit ultraviolet light, visible light, or infrared light, and may emit ultraviolet light, for example. The semiconductor device 101 may include various electronic devices such as a light emitting device and a light receiving device. The light emitting device and the light receiving device may include a first conductivity type semiconductor layer, an active layer, and a second conductivity type semiconductor layer. The semiconductor device 101 according to this embodiment may be a light emitting device. The light emitting device emits light by recombination of electrons and holes, and the wavelength of the light can be determined by an energy band gap inherent to the material. Thus, the wavelength of the emitted light may vary depending on the composition of the material. The light emitting device may include a light emitting diode (LED).

The semiconductor device 101 may emit light when power is supplied to the first and second electrodes 141 and 143. Light emitted through the upper surface, the lower surface and the side surfaces of the semiconductor element 101 may be irradiated to the adjacent sensing material 51. The first and second sensor electrodes 41 and 43 can detect a change in impedance of the sensing member 51 attached to the protrusion 28 when light is irradiated from the semiconductor element 101 and external gas is sensed. The protrusion 28 can selectively apply the protrusion description and structure disclosed in the embodiment.

The gas sensor part 10A may be provided with a groove 108 between the semiconductor elements 101 and the insulating layer 31 may be extended to the groove 108 to be separated from the semiconductor element 101 You can give.

13 is a schematic configuration diagram of the semiconductor device of Fig.

13, a semiconductor device 101 includes a substrate 11, a first conductive semiconductor layer 121, an active layer 123, and a second conductive semiconductor layer 125 on the substrate 11 A light emitting structure layer 120, an electrode layer 131 on the light emitting structure layer 120, a first electrode 141 connected to the first conductive semiconductor layer 121, and a second conductive semiconductor layer 125, And a second electrode 143 connected to the second electrode 143.

The substrate 11 may be a substrate made of a conductive or insulating material, or a substrate made of a light-transmitting or non-light-transmitting material. The substrate 11 may be selected from the group consisting of a sapphire substrate (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ and GaAs. The substrate 11 can be used as a layer for supporting the light emitting element. The substrate 11 may be the substrate 11 of the gas sensor portion 10A disclosed in the embodiment.

On the substrate 11, at least one of a semiconductor layer, a buffer layer, and a first conductivity type semiconductor layer may be disposed. In the embodiment, the same semiconductor layer as the semiconductor layer 21 of the gas sensor unit 10A is disposed on the substrate 11.

The light emitting structure layer 120 may include compound semiconductors of group II to VI elements, for example, group II and group V compound semiconductors, or group III and group V compound semiconductors. The first conductivity type semiconductor layer 121 of the light emitting structure layer 120 is disposed on the substrate 11 and includes a first conductive type dopant and an n type dopant such as Si, Ge, Sn, Se, Te, . The first conductivity type semiconductor layer 121 includes a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + y? The first conductive semiconductor layer 121 may be a compound semiconductor of a group III-V element doped with a first conductive dopant, for example, GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. The first conductive semiconductor layer 121 may be formed as a single layer or a multilayer, but the present invention is not limited thereto.

The active layer 123 is disposed on the first conductive semiconductor layer 121 and selectively includes a single quantum well, a multiple quantum well (MQW), a quantum wire structure, or a quantum dot structure . The active layer 123 includes a well layer and a barrier layer period. The well layer comprises a composition formula of _{In x Al y Ga 1 -x- y} N (0≤x≤1, 0≤y≤1, 0≤x + y≤1), and wherein the barrier layer is In _x Al _y It may include a composition formula of _{Ga 1 -x- y N (0≤x≤1,} 0≤y≤1, 0≤x + y≤1). InGaN / AlGaN, InGaN / InGaN, AlGaN / AlGaN, GaN / AlGaN, InAlGaN / InAlGaN, AlGaAs / GaAs, InGaAs / GaAs, InGaP / GaP, InGaN / InGaN, InGaN / InGaN, , InP / GaAs pairs. The period of the well layer / barrier layer may be two or more cycles, and the barrier layer may be formed of a semiconductor material having a band gap wider than the band gap of the well layer. The active layer 123 may selectively emit light within a wavelength range from visible light to ultraviolet light, and may emit light having a peak wavelength of ultraviolet light or light having a peak wavelength of visible light. However, the present invention is not limited thereto.

The second conductive semiconductor layer 125 is disposed on the active layer 123 and doped with a second conductive dopant such as In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? y? 1, 0? x + y? 1). The second conductive semiconductor layer 125 may include at least one of compound semiconductors such as GaN, InN, AlN, InGaN, AlGaN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP and AlGaInP. The second conductive semiconductor layer 125 may be a p-type semiconductor layer, and the second conductive dopant may include Mg, Zn, Ca, Sr, and Ba as p-type dopants.

The electrode layer 131 may be a transparent layer or a reflective layer. The electrode layer 131 may be disposed on the second conductivity type semiconductor layer 125 and may be electrically connected to the second conductivity type semiconductor layer 125. The reflective material layer may be formed of a metal or an alloy including at least one of metals such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Or may be formed in multiple layers. The transparent layer may be formed of indium tin oxide (ITO), indium-zinc-oxide (IZO), indium-zinc-tin-oxide (IZTO), indium- Zinc-Oxide), IGTO (Indium-Gallium-Tin-Oxide), AZO (Aluminum-Zinc-Oxide), and ATO (Antimony-Tin-Oxide). The transparent layer and the reflective material layer may be laminated, but the present invention is not limited thereto.

Fig. 14 can be arranged with the reflection plate 160 on the gas sensor of Fig. The reflection plate 160 may include at least one of a metal material such as Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Cu, Au and Hf.

The reflection plate 160 may be spaced apart from the semiconductor element 101 and may reflect light emitted from the semiconductor element 101. For example, ultraviolet light can be reflected. The reflective plate 160 may have a hole 162 therein and the hole 162 may be a hole into which a gas detectable by the gas sensor according to the embodiment is introduced. The hole 162 may have a minimum size so that light emitted from the semiconductor element 101 is not leaked to the outside. The holes 162 may include at least one or more than two of the holes 162, and may be arranged so as to be overlapped with the region in which the protrusions 28 are disposed. The semiconductor device 101 and the gas sensor part 10A may have a sidewall for preventing leakage of light. A circuit board for power supply may be disposed below the semiconductor device 101 and the gas sensor unit 10A.

15 is a plan view of a gas sensor or a gas sensing device as a modification of the third embodiment.

Referring to FIG. 15, the gas sensor or the gas sensing device may include a plurality of gas sensor portions 10A and 10B and a semiconductor device 101. The first gas sensor part 10A is disposed on the first area of the substrate 11 and the first sensing material 51 is dispersed and disposed on the surfaces of the first projections 29, The second gas sensor portion 10B is disposed on the third region of the substrate 11 and the second sensing material 52 is disposed on the surface of the second projections 29A, May be disposed.

The first and second gas sensor portions 10A and 10B may optionally include the gas sensor disclosed in the embodiment (s) of FIGS. 1 to 11, and the description disclosed in the above embodiment will be referred to. For example, the first and second gas sensor units 10A and 10B include a semiconductor layer 21, a plurality of protrusions 29 and 29A on the semiconductor layer 21, and a plurality of protrusions 29 and 29A (51, 52). The first and second gas sensor units 10A and 10B include first and second sensor electrodes 41 and 43 and 42 and 44 connected to the semiconductor layer 21. The first and second gas sensor units 10A and 10B include a base substrate 11 (FIG. 12), and the semiconductor layer 21 may be disposed on a substrate. An insulating layer (21 in FIG. 12) may be disposed on the semiconductor layer 21.

The first to third regions may be different regions on the upper surface of the substrate. The second region may be disposed between the first and third regions. The first and second gas sensor units 10A and 10B may be disposed on at least one side of the side surfaces of the semiconductor device 101, at opposite sides thereof, or at different sides thereof.

The first and third regions where the first and second gas sensor units 10A and 10B are disposed may be smaller than the area of the second region where the semiconductor device 101 is disposed. Here, the semiconductor device 101 may include a substrate as shown in FIG. 12, or may be integrally disposed or separated on a substrate disposed below the gas sensor units 10A and 10B. The sensing material 51 and 52 may be formed of a material for sensing different gases. For example, the sensing materials 51 and 52 may detect H ₂ S gas in the case of SnO ₂ -Fe and detect H ₂ gas in the case of SnO ₂ -Pd. Can detect CO ₂ or CO in the case of TiO ₂ -Cu, and detect HCl or Cl ₂ gas in the case of SnO ₂ O-Cu. The first and second sensing materials 51 and 52 may be sensing materials for sensing gases of different kinds.

A semiconductor device 101 may be disposed between the first and second gas sensor units 10A and 10B. The semiconductor device 101 may include, for example, the structure of FIG. 13, and may emit ultraviolet light, visible light, or infrared light, and may emit ultraviolet light, for example.

The first and second sensing members 51 and 52 may be disposed on the surfaces of the first and second protrusions 29 and 29A. The first sensing material 51 is attached to the surface of the first projection 29 and reacts with light emitted from the semiconductor element 101 and an external gas such as H ₂ S, The electrodes 41 and 43 can detect a change in impedance of the first sensing material 51. The second sensing material 52 is attached to the surface of the second projection 29A and reacts with light emitted from the semiconductor element 101 and an external gas such as HCl, , 44) can detect a change in impedance caused by the second sensing material (52).

The first and second gas sensor units 10A and 10B and the semiconductor device 101 may be disposed on a substrate (11 in FIG. 14) or separately from each other.

16 is a side cross-sectional view of the gas sensing device according to the fourth embodiment.

16, a gas sensing device 100 includes a circuit board 150, a gas sensor 10 on the circuit board 150, a semiconductor device 101A on the circuit board 150, A reflecting sidewall 110 surrounding the semiconductor device 10 and the semiconductor device 101A and a reflecting plate 160 on the reflecting sidewall 155. [ Although the gas sensor 10 and the semiconductor device 101A are described as being separated from each other, they may be realized by a gas sensor as shown in FIG. 12 or 14, but the invention is not limited thereto.

The circuit board 150 may include at least one of a resin-made PCB, a metal core PCB (MCPCB) having a metal core, and a flexible PCB (FPCB), but is not limited thereto. The circuit board 150 may include a ceramic material.

The reflective sidewalls 155 may be made of a ceramic material. The reflective sidewalls 155 may be formed of the same ceramic material as the circuit board 150. The circuit board 150 may include a plurality of circuit patterns (not shown) on an upper surface thereof, and the plurality of circuit patterns may be electrically connected to the gas sensor 10 and the semiconductor device 101A. The circuit pattern may be connected to the sensor electrodes of the gas sensor 10 by a wire or through another conductive member. The circuit pattern may be connected to the electrodes of the semiconductor element through a wire or may be directly bonded.

The gas sensor 10 and the semiconductor element 101A may be disposed inside the reflective sidewall 155. [ A reflective plate 160 is disposed on the reflective sidewall 155. The reflective plate 160 reflects light to prevent leakage of light. The inside of the reflective sidewall 155 may be formed with a cavity structure or a concave recessed structure. A stepped structure is disposed around the upper portion of the reflective sidewall 155, and the reflective plate 160 can be closely coupled to the stepped structure. The reflective plate 160 may be in contact with the reflective sidewall 155 with an adhesive (not shown).

The gas sensor 10 can detect gas exposure by the light irradiated from the semiconductor element 101A and the gas introduced through the hole 162 of the reflection plate 160, for example, a harmful gas.

Although the semiconductor device 101A and the gas sensor 10 are separately disposed on the circuit board 150, the semiconductor device 101A may be disposed on the substrate of the gas sensor 10 so as to be integrally disposed.

17 is a block diagram of a gas sensing system having a gas sensor according to an embodiment.

The impedance change sensed by the gas sensor 10 is detected by the signal processing circuit 171, and the signal processing circuit 171 detects the gas through a change in impedance due to the inflow of the gas. When the gas is detected, the signal processing circuit 171 can transmit the signal through the transmission module 175 by wire or wirelessly, or through the output module 177 through the alarm or display mode. The control unit 173 may be disposed in such a system. The control unit 173 can control the output or transmission of the signal processing circuit 171.

18 to 21 are views for explaining a process of manufacturing the gas sensor according to the embodiment.

Referring to FIG. 18, a semiconductor layer 21 may be grown on a substrate 11. The substrate 11 may be a conductive or insulating material. The substrate 11 may be a semiconductor substrate or a non-semiconductor substrate. The substrate 11 may be a light-transmitting or non-light-transmitting substrate. The substrate 11 may be selected from the group consisting of a sapphire substrate (Al ₂ O ₃ ), GaN, SiC, ZnO, Si, GaP, InP, Ga ₂ O ₃ and GaAs. The substrate 11 may be formed of a GaN-based semiconductor, for example, a GaN semiconductor. The substrate 11 may be a bulk GaN single crystal substrate. The substrate 11 may be used as a support member for supporting the gas sensor 10. [

The growth equipment of the semiconductor layer 21 may be an electron beam evaporator, a physical vapor deposition (PVD), a chemical vapor deposition (CVD), a plasma laser deposition (PLD), a dual-type thermal evaporator sputtering, , Metal organic chemical vapor deposition (MOCVD), or the like, but the invention is not limited thereto.

The semiconductor layer 21 may include a conductive semiconductor. The conductive semiconductor layer 21 may be an n-type semiconductor layer having an n-type dopant or a p-type semiconductor layer having a p-type dopant. The embodiment will be described as an example of the n-type semiconductor layer. The n-type dopant may include a dopant such as Si, Ge, Sn, Se, and Te. The semiconductor layer 21 may be disposed as a compound semiconductor of group II to VI elements. The semiconductor layer 21 may include at least one of group II and group V compound semiconductors and group III and group V compound semiconductors. The semiconductor layer 21 may be formed of at least one of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP, GaAs, GaAsP, AlGaInP, and ZnO. The semiconductor layer 21 may include a composition formula of In _x Al _y Ga _{1 -x- y} N (0? X? 1, 0? _Y? 1, 0? _X + y? The semiconductor layer 21 may include a GaN-based semiconductor. The semiconductor layer 21 may be a single layer or a multilayer, and may include a different semiconductor layer in the case of the multi-layer.

An insulating layer 31 may be formed on the semiconductor layer 21. The insulating layer 31 is the insulation layer 31 may be formed of a nitride or oxide-based insulating material, for example, SiNx (X> 0), SiO _2, SiO _x (X> 0), SiO _x N _y ( x > 9, y > 0) Si ₃ N ₄ , and Al ₂ O ₃ . If the insulating layer 31 is made of SiN, it may be formed of the same equipment as the semiconductor layer 21. This insulating layer 31 may be formed or formed by a deposition equipment. The insulating layer 31 may be deposited as a mask layer for blocking the growth of the semiconductor layer 21.

Thereafter, a plurality of first openings 33 are formed in the insulating layer 31. The first opening 33 may be formed through a predetermined mask pattern. The first opening 33 may have a circular shape, a polygonal shape, a long shape in any one direction, or a lower shape of the projection of the above-described embodiments.

Referring to FIG. 19, when the first opening 33 of the insulating layer 31 is formed, the semiconductor is grown through the semiconductor growth equipment, and the protrusions 23 are formed through the first opening 33 Can be grown from the semiconductor layer (21). The lower portions of the protrusions 23 are grown in accordance with the shape of the first openings 33. The protrusions 23 may be formed in a vertical column shape or a pyramid shape on the first openings 33 according to a growth method . The shape of the projection 23 will be described with reference to the description of the embodiments disclosed above.

Referring to FIG. 20, when the protrusion 23 is formed, the second and third openings 35 and 37 are disposed in the insulating layer 31, And two sensor electrodes 41 and 43 are formed. Referring to FIG. 21, when the first and second sensor electrodes 41 and 43 are formed, a sensing material 51 prepared in advance is deposited on the surface of the protrusion 23 and sintered. The sensing material 51 may be dispersed in an area of 10% or more of the exposed surface of the protrusion 23 in the form of a grain. The sensing material 51 may also be attached to the upper surface of the insulating layer 31. The material of the sensing material 51 will be described with reference to the description of the embodiments described above. The sensing material 51 may be selected depending on the type of the gas sensor, but is not limited thereto. Here, the process of forming the first and second sensor electrodes 41 and 43 and the process of forming the sensing material 51 may be changed.

The gas sensor or the gas sensor device according to the embodiment can be applied to a place where gases such as various kinds of toxic gas or explosive gas are generated, or to a space where the device is applied to a mobile device such as a vehicle lamp or an enclosed space. Or to an indoor or outdoor gas sensor device.

The features, structures, effects, and the like described in the embodiments are included in at least one embodiment and are not necessarily limited to only one embodiment. Furthermore, the features, structures, effects and the like illustrated in the embodiments can be combined and modified by other persons skilled in the art to which the embodiments belong. Accordingly, the contents of such combinations and modifications should be construed as being included in the scope of the embodiments.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. It can be seen that the modification and application of branches are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that the present invention may be embodied in many other specific forms without departing from the spirit or essential characteristics thereof.

10: Gas sensor
10A, 10B: gas sensor unit
11: substrate
21: semiconductor layer
23: projection
31: Insulating layer
41, 42, 43, 44:
51: Sensing material
101, 101A: Semiconductor device
120: light emitting structure layer
121: a first conductivity type semiconductor layer
123: active layer
125: second conductive type semiconductor layer
131: electrode layer
141, 143:

Claims (20)

Board;
A gas sensor disposed on a first region of the substrate; And
And a semiconductor device disposed on a second region of the substrate,
The gas sensor unit includes:
A semiconductor layer having a plurality of projections;
A sensing member disposed on the projection; And
And first and second sensor electrodes electrically connected to the semiconductor layer,
Wherein the semiconductor element includes a first conductivity type semiconductor layer, a second conductivity type semiconductor layer, and an active layer disposed between the first conductivity type semiconductor layer and the second conductivity type semiconductor layer. 2. The semiconductor device according to claim 1, further comprising an insulating layer disposed on the semiconductor layer and having an opening in which the plurality of protrusions are disposed,
And the protrusion protrudes from the upper surface of the insulating layer. The gas sensor according to claim 2, wherein the sensing material is dispersed on the surface of the projections. The gas device according to claim 2, wherein a part of the projection includes at least one of a polygonal columnar shape, a circular columnar shape, and a pyramidal shape. The semiconductor light emitting device according to any one of claims 2 to 4, wherein the semiconductor layer and the first conductivity type semiconductor layer are separated from each other on the substrate,
Wherein the semiconductor layer is disposed between the substrate and the insulating layer. 5. The sensor device according to any one of claims 1 to 4, wherein the plurality of protrusions are disposed between the first sensor electrode and the second sensor electrode,
Wherein the first and second sensor electrodes are disposed on the semiconductor layer. 7. The gas sensor of claim 6, wherein the semiconductor layer comprises a semiconductor having an n-type dopant. 8. The gas sensor according to claim 7, wherein the semiconductor layer comprises at least one of group II and group V compound semiconductors and group III and group V compound semiconductors. 8. The gas sensor according to claim 7, wherein the protrusion includes the same semiconductor as the semiconductor layer. 7. The sensor according to claim 6, wherein the sensing material comprises a main sensing material and a catalyst,
The main sensing material is _{SnO 2, CuO, TiO 2,} In 2 O 3, ZnO, V 2 O 5, RuO 2, WO 3, ZrO 2, MoO 3, NiO, CoO, Fe 2 O 3, and AB ₂ O ₄ At least one, or two or more,
The catalyst may be selected from the group consisting of platinum, copper, rhodium, gold, palladium, iron, titanium, vanadium, chromium, nickel, (Al), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), silver (Ag), hafnium (Hf), tantalum , Tungsten (W), rhenium (Re), and iridium (Ir). The method of claim 10, wherein the sensing material generates electrons by ultraviolet light,
Wherein the semiconductor element emits ultraviolet light. 6. The gas sensor according to claim 5, wherein the sensing material is disposed with an area of 10% or more of the surface area of the protrusions protruding through the insulating layer. The gas sensor according to claim 5, wherein the protrusions have a long length in one direction. 14. The gas sensor of claim 13, wherein the protrusions are connected to each other. The gas sensor as claimed in claim 5, wherein the semiconductor element includes a first electrode connected to the first conductivity type semiconductor layer, and a second electrode connected to the second conductivity type semiconductor layer, and emits ultraviolet light. A circuit board;
A gas sensor disposed on a first region of the circuit board; And
And a semiconductor element disposed on a second region of the circuit board,
The gas sensor comprises:
A conductive semiconductor layer;
An insulating layer having a plurality of first openings on the semiconductor layer;
A plurality of protrusions protruding from the semiconductor layer through a first opening of the insulating layer;
A sensing material on the surface of the projection; And
And first and second sensor electrodes electrically connected to the semiconductor layer. 17. The gas sensing device according to claim 16, wherein the sensing material is dispersed and arranged in a shape of a grain on a surface of the projection. 18. The apparatus of claim 17, wherein the protrusions are disposed between the first and second sensor electrodes,
And a reflective plate having reflective sidewalls around the gas sensor and the semiconductor element, the gas sensor, and a hole for gas entry on the semiconductor element,
Wherein the semiconductor element irradiates ultraviolet light onto the sensing material. 19. The sensor according to any one of claims 16 to 18, wherein the sensing material comprises a main sensing material and a catalyst,
The main sensing material is _{SnO 2, CuO, TiO 2,} In 2 O 3, ZnO, V 2 O 5, RuO 2, WO 3, ZrO 2, MoO 3, NiO, CoO, Fe 2 O 3, and AB ₂ O ₄ At least one, or two or more,
The catalyst may be selected from the group consisting of platinum, copper, rhodium, gold, palladium, iron, titanium, vanadium, chromium, nickel, (Al), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), silver (Ag), hafnium (Hf), tantalum , Tungsten (W), rhenium (Re), and iridium (Ir). Forming a semiconductor layer having an n-type dopant on a substrate;
Forming an insulating layer on the semiconductor layer;
Forming a plurality of first openings in the insulating layer;
Forming a plurality of protrusions protruding from the semiconductor layer through the first opening;
Forming first and second sensor electrodes spaced apart from each other on the semiconductor layer; And
And dispersing and depositing a sensing material in the form of a grain on the surface of the projections.

Images