KR102559405B1 - Hydrogen sensor and method for fabricating thereof - Google Patents

Abstract

According to one aspect of the technical concept of the present disclosure, a hydrogen sensor including a substrate, first and second electrodes formed on the substrate, a graphene layer formed to be spaced apart from the first and second electrodes between the first and second electrodes, a plurality of platinum structures formed spaced apart from each other on the graphene layer, and a third electrode electrically connected to the graphene layer.

Description

Hydrogen sensor and manufacturing method thereof

The technical idea of the present disclosure relates to a hydrogen sensor and a manufacturing method thereof, and more particularly, to a hydrogen sensor capable of detecting low concentration hydrogen gas with low power and small size with high sensitivity and a manufacturing method thereof.

Recently, hydrogen has been actively developed and applied as one of future renewable energies such as aerospace, hydrogen vehicles, and fuel cells. Accordingly, in order to block the risk of explosion due to hydrogen leakage, there is a need to develop a small, lightweight, low-power, and highly sensitive hydrogen sensor.

In general, a semiconductor sensor using a metal oxide that detects hydrogen gas through a chemical reaction is used, but a separate heating equipment is required for the chemical reaction, so the sensor has a large volume and weight, and other gases other than the hydrogen gas to be detected. As it reacts with other gases, the selectivity for the detection target is also low.

Meanwhile, a transistor hydrogen sensor using a platinum material as a gate electrode is being studied for normal temperature operation of the hydrogen sensor. However, in forming a gate electrode made of a platinum material, there is a conflict between the requirement that the gate electrode must have a certain thickness to operate as a gate electrode and the requirement to have a thin thickness for diffusion of hydrogen ions, so that it is difficult to manufacture a highly sensitive hydrogen sensor capable of satisfying both characteristics.

A technical problem to be achieved by the technical spirit of the present disclosure is to implement a hydrogen sensor capable of sensing low-concentration hydrogen gas with high sensitivity with low power and small size, and a manufacturing method thereof.

The technical problem to be achieved by the technical idea of the present disclosure is not limited to the above-mentioned problem, and another problem not mentioned above will be clearly understood by those skilled in the art from the description below.

In order to achieve the above object, according to an aspect according to the technical idea of the present disclosure, the substrate; first and second electrodes formed on the substrate; a graphene layer formed between the first and second electrodes and spaced apart from the first and second electrodes; a plurality of platinum structures formed spaced apart from each other on the graphene layer; And a third electrode electrically connected to the graphene layer; including, a hydrogen sensor is disclosed.

According to an exemplary embodiment, the graphene layer may include a plurality of irregular regions in which carbon atoms are arranged in a structure other than a hexagonal lattice.

According to an exemplary embodiment, the plurality of irregular regions may be formed with a period greater than a lattice period of a hexagonal lattice of carbon atoms of the graphene layer.

According to an exemplary embodiment, the plurality of platinum structures may be formed on the plurality of irregular regions.

According to an exemplary embodiment, the plurality of platinum structures may contact the upper surface of the graphene layer.

According to an exemplary embodiment, the plurality of platinum structures may have a thickness of 1 nm to 10 nm.

According to an exemplary embodiment, the third electrode may not be disposed between the first and second electrodes.

According to another aspect according to the technical spirit of the present disclosure, a substrate; first and second electrodes formed on the substrate; a graphene layer formed between the first and second electrodes and spaced apart from the first and second electrodes and including a plurality of irregular regions in which carbon atoms are arranged in a structure other than a hexagonal lattice; a plurality of metal structures respectively formed on the plurality of irregular regions of the graphene layer and spaced apart from each other; and a third electrode connected to the graphene layer.

According to an exemplary embodiment, the plurality of metal structures may include platinum.

According to an exemplary embodiment, the plurality of irregular regions may be formed with a period greater than a lattice period of a hexagonal lattice of carbon atoms of the graphene layer.

According to an exemplary embodiment, the plurality of metal structures may have a thickness of 1 nm to 10 nm.

According to an exemplary embodiment, the third electrode may not be disposed between the first and second electrodes.

According to another aspect according to the technical spirit of the present disclosure, forming a graphene layer on a gate insulating layer on a substrate; etching the graphene layer such that the graphene layer remains only in a gate region spaced apart from the source and drain electrodes between the source and drain electrodes on the substrate; and forming a plurality of platinum structures spaced apart from each other on the graphene layer by depositing a platinum material on the graphene layer.

According to an exemplary embodiment, between the step of etching the graphene layer and the step of forming the plurality of platinum structures, forming a plurality of irregular regions in the graphene layer in which carbon atoms are arranged in a structure other than a hexagonal lattice; may further include.

According to an exemplary embodiment, the forming of the plurality of irregular regions may include forming the plurality of irregular regions in the graphene layer using plasma containing oxygen gas.

According to an exemplary embodiment, the forming of the plurality of irregular regions may use plasma containing an oxygen gas having a second concentration lower than the first concentration of the oxygen gas used in the etching of the graphene layer.

According to an exemplary embodiment, the forming of the plurality of platinum structures may include forming the plurality of platinum structures on the plurality of irregular regions.

According to an exemplary embodiment, the forming of the plurality of platinum structures may include forming the plurality of platinum structures to have a thickness of 1 nm to 10 nm.

According to embodiments according to the technical concept of the present disclosure, a hydrogen sensor capable of detecting low-concentration hydrogen gas with high sensitivity and a method for manufacturing the same can be implemented with low power and small size.

The effects obtainable by the embodiments according to the technical idea of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned above will be clearly understood by those skilled in the art from the description below.

A brief description of each figure is provided in order to more fully understand the figures cited in this disclosure.
1 is a perspective view schematically illustrating a hydrogen sensor according to a technical concept of the present disclosure.
2 is a plan view illustrating an embodiment of a hydrogen sensor according to the technical concept of the present disclosure.
3 is a graph comparing sensitivity according to hydrogen concentration between a hydrogen sensor according to the technical concept of the present disclosure and a general hydrogen sensor.
4A and 4B are graphs for explaining the sensitivity of the hydrogen sensor according to the technical concept of the present disclosure.
5A is a plan view illustrating another embodiment of a hydrogen sensor according to the technical concept of the present disclosure.
FIG. 5B is an enlarged view of portion M of FIG. 5A.
FIG. 5C is a cross-sectional view of the hydrogen sensor viewed along line AA of FIG. 5A.
6 is a flow chart for explaining an embodiment of a method for manufacturing a hydrogen sensor according to the technical concept of the present disclosure.
7 is a flow chart for explaining an embodiment of a method for manufacturing a hydrogen sensor according to the technical idea of the present disclosure.

Exemplary embodiments according to the technical idea of the present disclosure are provided to more completely explain the technical idea of the present disclosure to those skilled in the art, and the following embodiments can be modified into various other forms, and the scope of the technical idea of the present disclosure is not limited to the following examples. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the spirit of the disclosure to those skilled in the art.

In the present disclosure, terms such as first and second are used to describe various members, regions, layers, regions, and/or components, but these members, parts, regions, layers, regions, and/or components are not limited by these terms. These terms do not imply any particular order, top or bottom, or superiority or inferiority, and are used only to distinguish one member, region, region, or component from another member, region, region, or component. Accordingly, a first member, region, region, or component to be described in detail below may refer to a second member, region, region, or component without departing from the teachings of the technical concept of the present disclosure. For example, a first element may be termed a second element, and similarly, the second element may be termed a first element, without departing from the scope of the present disclosure.

Unless defined otherwise, all terms used herein, including technical terms and scientific terms, have the same meaning as commonly understood by those of ordinary skill in the art to which the concepts of the present disclosure belong. In addition, commonly used terms as defined in a dictionary should be interpreted as having a meaning consistent with what they mean in the context of the related technology, and should not be interpreted in an excessively formal meaning unless explicitly defined herein.

When an embodiment is otherwise implementable, a specific process sequence may be performed differently from the described sequence. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order reverse to the order described.

In the accompanying drawings, variations of the shapes shown may be expected, eg depending on manufacturing techniques and/or tolerances. Therefore, embodiments according to the technical spirit of the present disclosure should not be construed as being limited to the specific shape of the region shown in the present disclosure, and should include, for example, changes in shape caused during manufacturing. The same reference numerals are used for the same components in the drawings, and duplicate descriptions thereof are omitted.

The term 'and/or' as used herein includes each and every combination of one or more of the recited elements.

Hereinafter, embodiments according to the technical idea of the present disclosure will be described in more detail with reference to the accompanying drawings.

1 is a perspective view schematically illustrating a hydrogen sensor according to a technical concept of the present disclosure. 2 is a plan view illustrating an embodiment of a hydrogen sensor according to the technical concept of the present disclosure.

1 and 2, the hydrogen sensor 100 may include a substrate 101, a semiconductor layer 103, a gate insulating layer 105, a graphene layer 107, a plurality of island-like structures 109, first and second electrodes 111a and 111b, and a third electrode 113 (hereinafter referred to as a gate electrode).

Unlike conventional gate electrodes, the hydrogen sensor 100 of the present disclosure has a structure in which a region forming a channel and a region connected to wires are separated, and a material and structure that organically connects both regions while improving functions in each region. In other words, in the region where the channel is formed, the graphene layer 107 having high electrical conductivity and a plurality of island-like structures 109 made of platinum (Pt) as a material that triggers the decomposition of the hydrogen gas (H2) are shallowly formed. Therefore, low concentration hydrogen gas (H2) can be sensed with high sensitivity. At the same time, since the gate electrode 113 having a predetermined thickness or more is formed in the region where the wires are connected, a structure capable of ensuring stable electrical connection may be obtained. Hereinafter, each structure will be described in detail.

The substrate 101 may be made of various materials, and may be, for example, a semiconductor substrate or a plastic substrate, but is not limited thereto.

The semiconductor layer 103 is formed on the substrate 101 and may include a plurality of semiconductor layers or a plurality of regions having different conductivity. For example, the semiconductor layer 103 may have a structure in which a GaN layer and an AlGaN layer are sequentially stacked, but is not limited thereto.

In the semiconductor layer 103, a channel is formed between the first and second electrodes 111a and 111b by a hydrogen reaction between the graphene layer 107 and the plurality of island-like structures 109 disposed thereon with the gate insulating layer 105 interposed therebetween.

The gate insulating layer 105 may be formed across the substrate 101 and the semiconductor layer 103, and is formed to insulate the semiconductor layer 103 described above, the graphene layer 107 described later, and the plurality of island-like structures 109. The gate insulating layer 105 may include silicon oxide, silicon nitride, or the like, but is not limited thereto.

The graphene layer 107 is formed on the gate insulating layer 105 and may have a thin thickness ranging from one carbon atom to several atomic layers. As the graphene layer 107 has a small thickness, it may have high electrical conductivity unique to graphene. In FIG. 1, the graphene layer 107 is illustrated as being made of only one atomic layer, but is not limited thereto and may be made of a plurality of layers.

The graphene layer 107 may be transferred using a thermal release tape (TRT) film or the like, but is not limited thereto. The graphene layer 107 may be formed through various processes such as chemical vapor deposition (CVD) and epitaxial growth.

The plurality of island-like structures 109 are made of a hydrogen decomposition catalyst material, for example, platinum (Pt), and are spaced apart from each other on the graphene layer 107 to have a width and a thickness of several nanometers (nm). Since platinum decomposes hydrogen gas (H2) at room temperature to form hydrogen ions (H+), the hydrogen sensor 100 can operate at room temperature. Specifically, the decomposed hydrogen ions (H+) move to the interface between the graphene layer 107 and the gate insulating layer 105 and apply a bias to the gate electrode 113 to generate a change in threshold voltage, thereby driving the hydrogen sensor 100. On the other hand, the plurality of island-type structures 109 are separate structures, and have a larger surface area than a layer structure or a film-type structure, enabling highly sensitive hydrogen detection even when exposed to a low concentration of hydrogen gas (H2). In addition, the plurality of island-like structures 109 are formed to a thin thickness of about 1 nm to 10 nm to provide a short diffusion distance of hydrogen ions (H+), so that even a low concentration of hydrogen ions (H+) causes a change in threshold voltage, enabling highly sensitive hydrogen sensing.

The plurality of island-like structures 109 may be formed on the graphene layer 107 using platinum as a deposition material and using a physical or chemical vapor deposition method. Specifically, sputtering, thermal evaporation, E-beam evaporation, electroplating, and spraying a metal aqueous solution on the sample surface may be used.

At this time, it may be deposited in the form of an island-like structure dispersed through a crystal nucleation process on the graphene layer 107 . When the graphene layer 107 includes irregular regions in which carbon atoms are arranged in a non-hexagonal lattice structure, crystal nucleation of the platinum material may be accelerated in the irregular regions.

Depending on the embodiment, the graphene layer 107 may include a plurality of irregular regions generated through a process of inducing a plurality of irregular regions, and island-like structures 109 may be formed on each of the plurality of irregular regions. It may have a structure. This will be described in detail with reference to FIGS. 5A to 5C.

The first and second electrodes 111a and 111b are formed on both sides of the semiconductor layer 103, respectively, and may be a drain electrode and a source electrode, respectively, or a source electrode and a drain electrode, respectively. The first and second electrodes 111a and 111b may include graphene, CNTs, or a metal such as Ag, Au, Pt, or Cu, but are not limited thereto.

The gate electrode 113 is disposed on the gate insulating layer 105 in a region other than between the first and second electrodes 111a and 111b and is electrically connected to an external wire. Since the gate electrode 113 is formed to a predetermined thickness or more in a region other than the channel region between the first and second electrodes 111a and 111b, connectivity with wiring is increased and at the same time, it is electrically and stably connected to the graphene layer 107 having a thin thickness formed in the channel region. Therefore, it can contribute to the high sensitivity response of the hydrogen sensor 100.

The gate electrode 113 may be made of platinum, but is not limited thereto, and may include various conductive materials. For example, the gate electrode 113 may include a metal such as Ag, Au, Pt, or Cu.

3 is a graph comparing sensitivity (S) according to hydrogen concentration (H2 concentration, ppm) of the hydrogen sensor 100 according to the technical concept of the present disclosure and a general hydrogen sensor.

1 to 3 together, in the gate region between the first and second electrodes 111a and 111b, when a structure (Pt/Gr) composed of a graphene layer 107 according to the present disclosure and a plurality of island-like structures 109 made of platinum is used for hydrogen detection, a 20 nm thick platinum gate electrode (20 nm Pt) and a 10 nm thick platinum gate electrode (10 nm Pt) are used in a general case It can be seen that the sensitivity is remarkably high over the entire concentration range of hydrogen gas.

Specifically, when the hydrogen concentration (H2) is 1 ppm, a hydrogen sensor using a 10 nm thick platinum gate electrode (10 nm Pt) has a sensitivity of about 1, whereas the hydrogen sensor 100 according to the present disclosure has a sensitivity of about 10 or more, and the sensitivity is improved by 10 times or more. In addition, for a hydrogen gas with a concentration of 100 ppm or more, the hydrogen sensor 100 of the present disclosure shows a sensitivity improvement of at least about 100 times and at least about 100,000 times as compared to a hydrogen sensor using a 10 nm thick platinum gate electrode (10 nm Pt). That is, in the case of using a generally known gate electrode structure in the gate region between the first and second electrodes 111a and 111b, even if a gate electrode made of platinum is used, since hydrogen ions that can move to the interface between the gate electrode and the gate insulating layer are reduced, it is confirmed that a significant difference occurs in the detection sensitivity of hydrogen gas compared to the present disclosure.

4A and 4B are graphs for explaining the sensitivity of the hydrogen sensor 100 according to the technical concept of the present disclosure.

Referring to FIGS. 4A and 4B , the hydrogen sensor 100 of the present disclosure is capable of detecting hydrogen gas according to a change in threshold voltage even when exposed to a low concentration of hydrogen gas of several ppm to several tens of ppm of about 1 ppm, 5 ppm, and 20 ppm. In addition, the hydrogen sensor 100 shows a very low reactivity to gases other than hydrogen gas and has a high selectivity to hydrogen gas. That is, when the hydrogen sensor 100 is exposed to other gases such as ammonia gas (NH3), hydrogen sulfide gas (HS), and carbon monoxide (CO) at a concentration of about 100 ppm, the hydrogen gas (H2) has a sensitivity of about 1/00 or less compared to the case where it is exposed to a concentration of about 100 ppm, so that the problem of malfunction due to a gas that is not a detection target is significantly reduced.

5A is a plan view illustrating another embodiment of a hydrogen sensor according to the technical concept of the present disclosure. FIG. 5B is an enlarged view of portion M of FIG. 5A. FIG. 5C is a cross-sectional view of the hydrogen sensor viewed along the line A-A of FIG. 5A.

The hydrogen sensor 200 of FIG. 5A is similar to the hydrogen sensor 100 of FIG. 2, but at least a portion of a plurality of irregular regions in which carbon atoms are arranged in a structure other than a hexagonal lattice in the graphene layer 207. It is different in that it is arranged periodically. The same reference numerals as in FIGS. 1 and 2 mean the same members, and duplicate descriptions are omitted.

Referring to FIGS. 1 and 5A to 5C, the graphene layer 207 has a basic structure in which carbon atoms are regularly planarly arranged in a hexagonal lattice, and at the same time, carbon in some areas of the hexagonal lattice is lost or added. It may include an irregular region (IR). Such an irregular region IR may be a deposition starting point for inducing crystal nucleation of platinum when a platinum material is deposited on the graphene layer 207 . Accordingly, a plurality of island-like structures 209 made of platinum may be respectively formed on the irregular regions IR of the graphene layer 207 .

In some embodiments, a plurality of irregular regions (IR) are artificially induced in the graphene layer 207 in a process of forming the graphene layer 207 or a subsequent process. The graphene layer 207 manufactured according to this process may include a plurality of periodically arranged irregular regions (IR), and accordingly, the hydrogen sensor 200 has a structure in which island-shaped structures 209 made of platinum are formed at a high density. In this case, the plurality of irregular regions IR may be formed with a period D2 greater than the lattice period D1 of the hexagonal lattice of carbon atoms of the graphene layer 207 . Accordingly, characteristics such as high electrical conductivity may be maintained due to the regular structure of the graphene layer 207, that is, the hexagonal lattice structure. However, it is not limited thereto, and at least some of the plurality of irregular regions IR may have periodicity, or all of the plurality of irregular regions IR may not be periodically arranged.

Meanwhile, the irregular regions IR of the graphene layer 207 may have any shape that does not conform to a structure in which carbon atoms are regularly arranged in a plane in a hexagonal lattice. As illustrated in FIGS. 5A to 5C , it may be a form in which one carbon atom in a hexagonal lattice is lost, but is not limited thereto, and may include any form not having a hexagonal lattice structure. For example, the irregular regions IR may include a form in which a plurality of consecutive carbon atoms are lost or a form in which a hexagonal lattice is deformed planarly or vertically by adding carbon atoms. In addition, it may include a form in which the arrangement of carbon atoms is rotated.

As described above, the thickness H207 of the graphene layer 207 and the thickness H209 of each of the plurality of island-like structures 209 may have a thickness of approximately several nanometers to several tens of nanometers. Also, the thickness H207 of the graphene layer 207 and the thickness H209 of the plurality of island-like structures 209 are smaller than the thickness H113 of the gate electrode 113 . Accordingly, even when the hydrogen sensor 200 is exposed to a low concentration of hydrogen gas (H2), hydrogen ions (H+) may diffuse into the inside using a short diffusion distance, thereby exhibiting high reactivity.

6 is a flowchart for explaining an embodiment of a method of manufacturing the hydrogen sensor 100 according to the technical idea of the present disclosure. In the description of FIG. 6, but described with reference to FIGS. 1 and 2 together, since the same reference numerals denote the same members, overlapping descriptions will be omitted.

Referring to FIGS. 1 , 2 and 6 , first, a semiconductor layer 103 on a substrate 101 and a gate insulating layer 105 are formed in a region where a channel is to be formed among the semiconductor layer 103 . First and second electrodes 111a and 111b are formed on both sides of the gate region, respectively.

Subsequently, a graphene layer 107 is formed on the gate insulating layer 105 (S101).

The graphene layer 107 may be transferred using a thermal release tape (TRT) film or the like, but is not limited thereto. The graphene layer 107 may be formed through various methods such as chemical vapor deposition (CVD) and epitaxial growth.

The graphene layer 107 is etched through a photolithography process and an oxygen gas plasma treatment so that the graphene layer 107 remains only in the gate region spaced apart from the first and second electrodes 111a and 111b between the first and second electrodes 111a and 111b (S103).

After forming the graphene layer 107, a photoresist layer exposing only the upper surface of the graphene layer 107 is formed in the gate region between the first and second electrodes 111a and 111b (S105).

A plurality of island-shaped structures 109 spaced apart from each other may be formed by depositing a platinum material on the exposed graphene layer 107 (S107). In this case, the plurality of island-like structures 109 may be formed to a thickness of several nanometers or more, for example, 1 nm to 10 nm.

The plurality of island-like structures 109 may be formed on the graphene layer 109 using a physical or chemical vapor deposition method using platinum as a deposition material. Specifically, sputtering, thermal evaporation, E-beam evaporation, electroplating, and spraying a metal aqueous solution on the sample surface may be used.

In this case, platinum may be deposited on the graphene layer 107 in the form of an island-like structure dispersed through a crystal nucleation process. Irregular regions (eg, defect regions) in which carbon atoms are arranged in a structure other than a hexagonal lattice are included in the graphene layer 107 through the formation of the graphene layer 107 and the etching process of the graphene layer 107. If the graphene layer 107 includes irregular regions, crystal nucleation of the platinum material may be accelerated.

Subsequently, the hydrogen sensor 100 may be manufactured by lifting off the photoresist layer and forming the gate electrode 113 (S109).

7 is a flowchart for explaining an embodiment of a method of manufacturing a hydrogen sensor 200 according to the technical concept of the present disclosure. In the description of FIG. 7, it will be described with reference to FIGS. 1 and 5A to 5C, but since the same reference numerals denote the same members, overlapping descriptions will be omitted.

The manufacturing method (F200) of the hydrogen sensor 200 of FIG. 7 is similar to the manufacturing method (F100) of the hydrogen sensor 100 of FIG.

Referring to FIGS. 1, 5A to 5C, and 7 , a substrate 101, a semiconductor layer 103, a gate insulating layer 105, and a graphene layer 207 are formed, and the graphene layer 207 is only on the gate insulating layer 105. Etching is performed so that the layer 207 remains (S201, S203).

A photoresist layer exposing only the upper surface of the graphene layer 207 is formed (S205), and a plurality of irregular regions IR are formed on the exposed upper surface of the graphene layer 207 (S207).

For example, surface treatment may be performed on the upper surface of the graphene layer 207 using plasma having a predetermined oxygen concentration, and accordingly, a plurality of irregular regions IR may be formed in the graphene layer 207 instead of a hexagonal lattice structure of carbon atoms. Meanwhile, when a plasma etching process having a first oxygen concentration is used in etching the graphene layer 207 in step S203, a plasma having a second oxygen concentration lower than the first oxygen concentration may be used in step S207.

Meanwhile, the process of forming the irregular regions IR is not implemented only by performing a separate plasma treatment process as in step S207. Depending on the embodiment, the irregular regions IR may be formed by adjusting at least one condition, such as pressure, temperature, input material concentration in the chamber, plasma gas concentration, electric field size, etc., in the forming of the graphene layer 207 in steps S201 and S203, the etching process, and the photoresist layer forming process in step S205.

Subsequently, a plurality of island-shaped structures 209 may be formed on the plurality of irregular regions IR by depositing a platinum material (Pt) on the graphene layer 207 (S209). As described above with reference to FIG. 6 , as the graphene layer 207 includes irregular regions IR in which carbon atoms are arranged in a non-hexagonal lattice structure, crystal nucleation of the platinum material Pt may be accelerated in the irregular regions IR.

Thereafter, the hydrogen sensor 200 may be manufactured by lifting off the photoresist layer and forming the gate electrode 113 (S211).

Since the description of the above embodiments is only examples with reference to the drawings for a more thorough understanding of the present disclosure, it should not be construed as limiting the technical spirit of the present disclosure.

In addition, it will be clear to those skilled in the art that various changes and modifications are possible within a range that does not deviate from the basic principles of the present disclosure.

100, 200: hydrogen sensor
101: substrate
103: semiconductor layer
105: gate insulating layer
107, 207: graphene layer
109, 209: island type structure
111a, 111b: first and second electrodes
113: gate electrode
IR: Irregular area
PT: Platinum
F100, F200: Manufacturing method of hydrogen sensor

Claims (18)

Board;
a semiconductor layer formed on the substrate;
a gate insulating layer formed on the semiconductor layer across the substrate and the semiconductor layer;
first and second electrodes formed on the substrate;
a graphene layer formed on the gate insulating layer and spaced apart from the first and second electrodes between the first and second electrodes;
a plurality of platinum structures formed spaced apart from each other on the graphene layer; and
a third electrode disposed on the gate insulating layer in a region not between the first and second electrodes and electrically connected to the graphene layer;
Including, hydrogen sensor.
According to claim 1,
The graphene layer includes a plurality of irregular regions in which carbon atoms are arranged in a non-hexagonal lattice structure.
According to claim 2,
The plurality of irregular regions are formed with a period greater than a lattice period of a hexagonal lattice of carbon atoms of the graphene layer.
According to claim 2,
The plurality of platinum structures are formed on the plurality of irregular regions.
According to claim 1,
The plurality of platinum structures are in contact with the upper surface of the graphene layer, the hydrogen sensor.
According to claim 1,
Wherein the plurality of platinum structures have a thickness of 1 nm to 10 nm.
delete Board;
a semiconductor layer formed on the substrate;
a gate insulating layer formed on the semiconductor layer across the substrate and the semiconductor layer;
first and second electrodes formed on the substrate;
a graphene layer formed on the gate insulating layer, disposed between the first and second electrodes and spaced apart from the first and second electrodes, and including a plurality of irregular regions in which carbon atoms are arranged in a structure other than a hexagonal lattice;
a plurality of metal structures respectively formed on the plurality of irregular regions of the graphene layer and spaced apart from each other; and
a third electrode disposed on the gate insulating layer in a region not between the first and second electrodes and electrically connected to the graphene layer;
Including, hydrogen sensor.
According to claim 8,
The plurality of metal structures include platinum, hydrogen sensor.
According to claim 8,
The plurality of irregular regions are formed with a period greater than a lattice period of a hexagonal lattice of carbon atoms of the graphene layer.
According to claim 8,
Wherein the plurality of metal structures have a thickness of 1 nm to 10 nm.
delete forming a semiconductor layer on a substrate;
forming a gate insulating layer on the semiconductor layer crossing the substrate and the semiconductor layer;
forming a graphene layer on the gate insulating layer;
etching the graphene layer such that the graphene layer remains only in a gate region spaced apart from the source and drain electrodes between the source and drain electrodes on the substrate; and
Depositing a platinum material on the graphene layer to form a plurality of platinum structures spaced apart from each other on the graphene layer;
A method of manufacturing a hydrogen sensor, wherein a gate electrode is formed on the gate insulating layer in a region other than between the source electrode and the drain electrode.
According to claim 13,
Between the step of etching the graphene layer and the step of forming the plurality of platinum structures,
forming a plurality of irregular regions in the graphene layer in which carbon atoms are arranged in a structure other than a hexagonal lattice;
Further comprising a method for manufacturing a hydrogen sensor.
According to claim 14,
Forming the plurality of irregular regions,
Forming the plurality of irregular regions in the graphene layer using plasma containing oxygen gas, a method of manufacturing a hydrogen sensor.
According to claim 15,
Forming the plurality of irregular regions,
A method of manufacturing a hydrogen sensor using plasma containing an oxygen gas having a second concentration lower than the first concentration of the oxygen gas used in the step of etching the graphene layer.
According to claim 14,
Forming the plurality of platinum structures,
Forming the plurality of platinum structures on the plurality of irregular regions.
According to claim 13,
Forming the plurality of platinum structures,
Forming the plurality of platinum structures to have a thickness of 1 nm to 10 nm, a method of manufacturing a hydrogen sensor.

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