Measurement of hydrogen gas

Abstract

One aspect of the present invention provides a method for measuring hydrogen gas, comprising the steps of: providing a hydrogen sensing sensor; introducing a gas containing hydrogen into the hydrogen sensing sensor; and measuring the hydrogen gas based on a change in the capacitance of the hydrogen sensing sensor, wherein the hydrogen sensing sensor comprises an insulating substrate, an oxide film layer laminated on the insulating substrate, a rubber substrate laminated on the oxide film layer, and a catalyst layer laminated on the rubber substrate.

Description

Technology Field

[0001] The present invention relates to a palladium rubber substrate capacitive hydrogen sensor and a method for measuring hydrogen gas using the same. More specifically, it relates to a PDMS thin-film and patterned hydrogen sensor capable of sensitively reacting to low-concentration hydrogen without being affected by contact resistance, and a hydrogen sensor that precisely detects hydrogen concentration through the measurement of capacitance. Background Technology

[0003] With the recent increase in demand for eco-friendly energy, hydrogen energy is garnering significant attention. Consequently, research into the storage, transportation, and utilization of hydrogen gas is active, leading to massive global investments. In particular, given that hydrogen is explosive in air, safety management is essential, making the role of hydrogen leak sensors critical.

[0004] Furthermore, with the recent rise in interest in health management beyond the energy industry, there has been increased interest in and a growing need for research on exhaled gas analysis. In particular, since hydrogen gas in exhaled air has the potential to serve as a biomarker for intestinal diseases, there is a possibility of diagnosis through the analysis of low-concentration hydrogen at the ppm level.

[0005] As described above, semiconductor hydrogen sensors, catalytic combustion hydrogen sensors, and gas thermal conductivity hydrogen sensors have been developed to detect hydrogen gas within specific concentration ranges for various purposes. Among these, semiconductor hydrogen sensors utilize the change in electrical properties resulting from the chemical bonding of hydrogen gas with an oxygen ion layer formed by the combination of oxygen vacancies in the surface of a metal oxide with oxygen in the air as their primary detection principle.

[0006] Furthermore, the selectivity and sensing performance for hydrogen gas can be enhanced by applying various catalytic metals. Consequently, maximizing the reaction surface area and utilizing appropriate catalytic metals are crucial for achieving high sensing performance, and extensive research has been conducted in this regard.

[0007] Among various hydrogen sensing materials, tin(II) oxide (SnO2) nanostructures have been widely utilized as gas sensor materials and have been continuously developed as a leading framework within the gas sensor research community. It is evident that SnO2 nanomaterials have established themselves as the most widely used material, accounting for nearly 30% of metal oxide semiconductor gas sensor usage. SnO2 is an n-type semiconductor with a tetragonal rutile structure and a wide bandgap of 3.6 eV. This provides a decisive advantage regarding the double valence of Sn on the surface, which depends on the oxygen chemical potential of Sn 4+ Sn on stoichiometric surfaces with cations 2+ The reduced surface with cations enables a reversible surface composition. The dual active sites on the SnO2 surface adsorb chemically different oxygen ions, namely O2, at different temperatures. - , O - and O 2- It promotes the formation of. Therefore, due to the surface characteristics of SnO2, a wide range of gases such as H2S, CO, NOx, liquefied petroleum gas (LPG, mainly propane and butane), methanol, NH3, and other low-concentration gases can be detected.

[0008] To be utilized as a hydrogen sensor, palladium metal, which exhibits excellent reactivity with hydrogen even at relatively room temperature compared to other metal catalysts, is primarily used as a catalyst by coating it onto tin oxide nanostructures to a thickness of several nanometers. By using such a palladium catalyst, selectivity compared to other gases can be enhanced when used as a gas sensor, and excellent hydrogen detection characteristics can be obtained even at relatively low operating temperatures; consequently, it is currently being utilized as a diverse hydrogen detection material.

[0009] These palladium (Pd) catalysts exhibit sensing performance by transitioning to PdHx through hydrogen adsorption on the palladium surface upon exposure to hydrogen gas at relatively low temperatures. In conventional hydrogen sensing sensors using palladium metal as a catalyst layer, if a hydrogen concentration of approximately 1 vol% enters the palladium catalyst, a transition from the alpha phase to the beta phase occurs and the volume expands; however, it is observed that concentration discrimination capability is lost due to the saturation of detection reactivity at hydrogen concentrations above 1%. Since the hydrogen gas explosion limit is a concentration of 4 vol%, concentration discrimination capability in the 1–4 vol% range is required. Furthermore, problems are emerging regarding the increasing error rate, as reactivity deteriorates during repeated reactions and exhibits an aging phenomenon where reactivity continuously increases during long-term reactions. Additionally, conventional hydrogen sensors utilizing palladium are at risk of substrate deformation due to stress caused by changes in the volume of palladium.

[0010] To address the aforementioned problems, it is necessary to develop a hydrogen sensor that detects hydrogen by measuring electrical capacitance, rather than the resistive hydrogen sensors used in conventional technology. Unlike conventional resistive hydrogen sensors, a hydrogen sensor that precisely detects hydrogen concentration through the measurement of electrical capacitance is not affected by contact resistance; therefore, it can detect the presence of low-concentration hydrogen more sensitively and operate broadband over a wide partial pressure range. The problem to be solved

[0012] Accordingly, the technical problem to be solved by the present invention is to provide a palladium rubber substrate hydrogen sensor that detects hydrogen by measuring electrical capacitance.

[0013] One embodiment of the present invention aims to provide a hydrogen sensor capable of resolving substrate deformation caused by stress due to volume changes of palladium in conventional hydrogen sensors using palladium, being unaffected by contact resistance, and sensitively detecting low-concentration hydrogen.

[0014] However, the technical problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art to which the present invention belongs from the description below. means of solving the problem

[0016] To achieve the above technical objective, one aspect of the present invention provides a method for measuring hydrogen gas, comprising: a step of providing a hydrogen sensing sensor; a step of introducing a gas containing hydrogen into the hydrogen sensing sensor; and a step of measuring hydrogen gas based on a change in the capacitance of the hydrogen sensing sensor, wherein the hydrogen sensing sensor comprises an insulating substrate, an oxide film layer laminated on the insulating substrate, a rubber substrate laminated on the oxide film layer, and a catalyst layer laminated on the rubber substrate.

[0017] The electrode width of the hydrogen sensing sensor may be 20 μm to 2 cm, and the thickness of the catalyst layer may be 5 to 300 nm.

[0018] The catalyst layer may be characterized by being laminated in a thin film form.

[0019] The catalyst layer may be characterized by being stacked in a patterned manner.

[0020] The above-described patterned stacked catalyst layer may be characterized by having a thickness of 7.5 to 50 nm when deposited at the same pattern interval, and a pattern interval of 40 to 320 μm when deposited at the same thickness.

[0021] It may be characterized by connecting the insulating substrate and the catalyst layer as electrodes, and connecting the oxide film layer and the rubber substrate as dielectrics to measure electrical capacitance.

[0022] The insulating substrate may be characterized as being a doped silicon substrate.

[0023] The catalyst layer may comprise any one selected from the group consisting of palladium (Pd), platinum (Pt), aluminum (Al), nickel (Ni), manganese (Mn), molybdenum (Mo), magnesium (Mg) and vanadium (V).

[0024] The catalyst layer may be characterized as being palladium (Pd).

[0025] The above rubber substrate may be characterized as being polydimethylsiloxane (PDMS).

[0026] The insulating substrate and the catalyst layer may be characterized by being connected by silver paste (Ag paste).

[0027] The catalyst layer laminated on the above rubber substrate may be characterized by adsorbing hydrogen gas and expanding its surface area.

[0029] Another aspect of the present invention provides a hydrogen sensing sensor sensed using the measurement method of claim 1, characterized by comprising: an insulating substrate; an oxide film layer laminated on the substrate; a rubber substrate laminated on the oxide film layer; and a catalyst layer laminated on the rubber substrate.

[0030] The catalyst layer may be characterized by being laminated in a thin film or patterned form.

[0031] The insulating substrate may be characterized as being a doped silicon substrate.

[0032] It may be characterized by connecting the insulating substrate and the catalyst layer as electrodes, and connecting the oxide film layer and the rubber substrate as dielectrics to measure electrical capacitance.

[0033] The catalyst layer may be palladium (Pd), and the rubber substrate may be characterized as being polydimethylsiloxane (PDMS). Effects of the invention

[0035] According to one aspect of the present invention, unlike conventional commercial hydrogen sensors, hydrogen can be detected by measuring capacitance rather than resistance. Since it is not affected by contact resistance unlike conventional resistive hydrogen sensors, the presence of low-concentration hydrogen can be detected more sensitively and it can operate broadband over a wide partial pressure range.

[0036] According to one aspect of the present invention, by fabricating a hydrogen sensor based on palladium that selectively adsorbs to hydrogen, it can have higher selectivity than a catalytic combustion type hydrogen sensor that reacts with most combustible gases and a metal oxide semiconductor hydrogen sensor that reacts with most reducing gases, and can have high mechanical / thermodynamic stability by relieving stress caused by volume change through the introduction of a rubber material.

[0037] According to one aspect of the present invention, since it does not have a sensing layer that is consumed like the electrolyte of an electrochemical sensor, it can theoretically have the advantage of being usable permanently except for mechanical damage, and since it predicts hydrogen partial pressure through electrical capacitance, it does not require external energy during the sensor operation and recovery process, so it can be efficient in terms of power consumption.

[0038] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the composition of the invention described in the description or claims of the present invention. Brief explanation of the drawing

[0040] FIG. 1 shows a cross-sectional view of a hydrogen detection sensor according to one embodiment of the present invention. FIG. 2 is a schematic diagram of a thin-film hydrogen sensing sensor according to one embodiment of the present invention. Figure 3 shows a schematic diagram of the expansion of the catalyst layer of a thin-film hydrogen sensing sensor according to one embodiment of the present invention. FIG. 4 is a schematic diagram of a patterned hydrogen detection sensor according to one embodiment of the present invention. FIG. 5 is a schematic diagram showing the expansion of the catalyst layer of a patterned hydrogen sensing sensor according to one embodiment of the present invention. FIGS. 6 and 7 illustrate a measurement system according to one embodiment of the present invention. FIG. 8 shows an example of hydrogen detection by a thin-film hydrogen sensing sensor according to one embodiment of the present invention. FIG. 9 shows an example of hydrogen detection by a pattern-type hydrogen detection sensor according to one embodiment of the present invention. Figure 10 is comparative data of hydrogen detection reactivity according to palladium deposition thickness of a patterned hydrogen detection sensor according to one embodiment of the present invention. Figure 11 is comparative data of hydrogen detection reactivity by palladium pattern of a patterned hydrogen detection sensor according to one embodiment of the present invention. FIG. 12 is a comparative example according to one embodiment of the present invention, showing a conventional hydrogen detection sensor. Figure 13 illustrates a sputtering and photolithography method for a palladium thin film or pattern in which randomness does not exist. Specific details for implementing the invention

[0041] The present invention will be described in more detail below with reference to the attached drawings. However, the present invention may be implemented in various different forms and is therefore not limited to the embodiments described herein. Furthermore, in order to clearly explain the present invention in the drawings, parts unrelated to the explanation have been omitted, and similar parts throughout the specification have been given similar reference numerals.

[0042] Throughout the specification, when it is stated that a part is "connected (connected, in contact, combined)" with another part, this includes not only cases where they are "directly connected," but also cases where they are "indirectly connected" with other members interposed between them. Furthermore, when it is stated that a part "includes" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but rather allows for the inclusion of additional components.

[0043] The terms used herein are merely for describing specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to indicate the presence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0044] In describing the present invention, if it is determined that a detailed description of related known configurations or functions could obscure the essence of the invention, such detailed description may be omitted.

[0046] The first aspect of the present invention provides a method for measuring hydrogen gas, comprising the steps of: providing a hydrogen sensing sensor; introducing a gas containing hydrogen into the hydrogen sensing sensor; and measuring the hydrogen gas based on a change in the capacitance of the hydrogen sensing sensor, wherein the hydrogen sensing sensor comprises an insulating substrate, an oxide film layer laminated on the insulating substrate, a rubber substrate laminated on the oxide film layer, and a catalyst layer laminated on the rubber substrate.

[0048] Hereinafter, a method for measuring hydrogen gas according to the first aspect of the present invention will be described. FIG. 1 is a cross-sectional view of a hydrogen detection sensor according to one embodiment of the present invention.

[0050] In one embodiment of the present invention, the width of the electrode of the hydrogen sensing sensor may be 20 μm to 2 cm, and the thickness of the catalyst layer may be 5 to 300 nm. If the width of the electrode or the thickness of the catalyst layer exceeds the ranges described above, capacitance measurement may not be performed smoothly.

[0051] In one embodiment of the present invention, the hydrogen sensing sensor may be fabricated by forming a thin film of PDMS, which has rubber-like properties of stretching in response to external stress, and coating it onto a doped silicon substrate, and by depositing a metallic palladium layer that has the property of expanding upon the adsorption of hydrogen on the PDMS layer. The palladium layer of the hydrogen sensing sensor may be fabricated as a thin film, or it may be fabricated as a pattern to more easily relieve stress due to changes in area and to expand more sensitively upon the adsorption of hydrogen.

[0052] In one embodiment of the present invention, the catalyst layer may be laminated in a thin film form, and a schematic diagram of a thin film hydrogen sensing sensor is shown through FIG. 2. FIG. 3 shows a schematic diagram of a metal palladium catalyst layer having the property of expanding upon the adsorption of hydrogen on a PDMS layer of a thin film hydrogen sensing sensor.

[0053] In one embodiment of the present invention, the catalyst layer may be stacked in a patterned manner, and a schematic diagram of a patterned hydrogen sensing sensor is shown through FIG. 4. A schematic diagram of the catalyst layer of the patterned hydrogen sensing sensor expanding is shown through FIG. 5.

[0054] In one embodiment of the present invention, the patterned stacked catalyst layer may have a thickness of 7.5 to 50 nm when deposited with the same pattern spacing, and a pattern spacing of 40 to 320 μm when deposited with the same thickness.

[0055] In one embodiment of the present invention, the insulating substrate and the catalyst layer may be connected as electrodes, and the oxide film layer and the rubber substrate may be connected as dielectrics to measure electrical capacitance, and the insulating substrate may be a doped silicon substrate.

[0056] In one embodiment of the present invention, the catalyst layer may comprise any one selected from the group consisting of palladium (Pd), platinum (Pt), aluminum (Al), nickel (Ni), manganese (Mn), molybdenum (Mo), magnesium (Mg) and vanadium (V), and most preferably palladium (Pd).

[0057] In one embodiment of the present invention, the rubber substrate may be polydimethylsiloxane (PDMS).

[0058] In one embodiment of the present invention, the insulating substrate and the catalyst layer may be connected by silver paste (Ag paste).

[0059] In one embodiment of the present invention, the catalyst layer laminated on the rubber substrate may expand in area by adsorbing hydrogen gas. Since a larger amount of hydrogen is adsorbed onto the palladium layer in a high-concentration hydrogen environment, the hydrogen concentration can be estimated through the change in the area of ​​the palladium layer. Additionally, capacitance has the property of increasing in proportion to the area of ​​two electrodes separated by a dielectric that does not conduct electricity. By using the oxide film of the silicon substrate and the PDMS layer thereon as the dielectric, and using the doped silicon layer and the palladium layer on the PDMS layer as the respective electrodes to measure the capacitance, this can provide a hydrogen gas measurement method that can estimate the area of ​​the palladium layer by measuring the capacitance between the two electrodes and sensitively read the current hydrogen concentration.

[0061] The present invention provides a hydrogen sensing sensor sensed using the measurement method of claim 1, characterized in that the second aspect comprises: an insulating substrate; an oxide film layer laminated on the substrate; a rubber substrate laminated on the oxide film layer; and a catalyst layer laminated on the rubber substrate.

[0063] Detailed explanations have been omitted for parts that overlap with the first aspect of the present invention, but the content described in the first aspect of the present invention may be applied equally even if such explanations are omitted in the second aspect.

[0065] Hereinafter, a hydrogen sensing sensor according to the second aspect of the present invention will be described in detail.

[0066] FIG. 1 is a cross-sectional view of a hydrogen sensing sensor according to one embodiment of the present invention.

[0068] First, in one embodiment of the present invention, the catalyst layer may be laminated in a thin film or a patterned form.

[0069] In one embodiment of the present invention, the insulating substrate may be a doped silicon substrate.

[0070] In one embodiment of the present invention, the insulating substrate and the catalyst layer are connected as electrodes, and the oxide film layer and the rubber substrate are connected as dielectrics to measure electrical capacitance.

[0071] In one embodiment of the present invention, the catalyst is palladium (Pd), and the rubber substrate may be polydimethylsiloxane (PDMS).

[0072] In one embodiment of the present invention, a “nanogap hydrogen sensor” is known as another type of conventional hydrogen sensing sensor that uses a rubber substrate and utilizes the phenomenon in which the area of ​​a palladium thin film increases in a hydrogen environment, and the manufacturing method and example are shown in FIG. 12. This sensor can detect the presence of hydrogen in the range of 0.05% to 4% based on the principle of electrically turning on or off. Meanwhile, in a hydrogen environment within the corresponding concentration range, repeatability cannot be guaranteed because the crack size of a gap that has been attached and detached changes easily compared to the time of previous hydrogen exposure, and since cracks caused by tension appear in different ways each time, identical performance and operation cannot be expected for each device. The measurement limit and sensitivity also depend directly on the widest gap among the various sizes of randomly occurring cracks, so reliability is low.

[0073] Meanwhile, the capacitance-based hydrogen detection sensor proposed in this patent does not read hydrogen based on the principle of turning it on or off, but rather reads the area that increases in proportion to the hydrogen concentration as the magnitude of the capacitance signal. This allows for operation in a much wider bandwidth and enables the implementation of a sensor capable of quantitatively reading the hydrogen concentration. Furthermore, as shown in FIG. 13, since palladium thin films or patterns are fabricated exclusively using sputtering and photolithography methods that do not involve randomness, the devices are fabricated under identical conditions, allowing for the control of their functions with high reliability. Consequently, each device can possess nearly identical performance and properties, making it much more advantageous for commercialization.

[0075] Hereinafter, embodiments of the present invention are described in detail so that those skilled in the art can easily implement the invention. However, the present invention may be embodied in various different forms and is not limited to the embodiments described herein.

[0077] Preparation Example 1: Thin-film hydrogen sensing sensor

[0078] First, as shown in Fig. 1, an insulating silicon substrate was prepared, and then an oxide film layer and a rubber substrate were sequentially deposited. The width of the electrode was set to approximately 50 μm and the length to approximately 1000 μm, and polydimethylsiloxane (PDMS) was used as the rubber substrate.

[0079] Finally, palladium (Pd) is deposited in a thin film form and coated as a stacked catalyst layer. Figures 2 and 3 show a schematic diagram of a thin-film hydrogen sensor and a schematic diagram of the expansion of the catalyst layer of the thin-film hydrogen sensor.

[0081] Preparation Example 2: Patterned hydrogen detection sensor

[0082] First, as shown in Fig. 1, an insulating silicon substrate was prepared, and then an oxide film layer and a rubber substrate were sequentially deposited. The width of the electrode was set to approximately 50 μm and the length to approximately 1000 μm, and polydimethylsiloxane (PDMS) was used as the rubber substrate.

[0083] Finally, palladium (Pd) is deposited in a patterned manner and coated as a stacked catalyst layer. Figures 4 and 5 show a schematic diagram of a thin-film hydrogen sensor and a schematic diagram of the expansion of the catalyst layer of the thin-film hydrogen sensor. At this time, when deposited with the same pattern spacing (40 μm), the deposited catalyst layers were fabricated with deposition thicknesses of 7.5 nm / 40 μm, 10 nm / 40 μm, 20 nm / 40 μm, 30 nm / 40 μm, 40 nm / 40 μm, and 50 nm / 40 μm, and when deposited with the same thickness (20 nm), they were fabricated with thicknesses of 20 nm / 40 μm, 20 nm / 80 μm, 20 nm / 160 μm, and 20 nm / 320 μm, respectively.

[0085] Example 1: Comparison of Reactivity and Resistance of Hydrogen Sensing Sensors by Concentration

[0086] The reactivity of the hydrogen detection sensor according to hydrogen concentration was measured through the measurement system shown in Figures 6 and 7. Hydrogen and nitrogen were prepared and introduced into a Mass Flow Controller (MFC) to control the flow rate, and the hydrogen and nitrogen were introduced into the hydrogen sensor in the test chamber by controlling the Mass Flow Controller. After that, the capacitance of the sensor element was measured in real time using an LCR meter and output.

[0087] Figure 8 shows the response graph according to hydrogen concentration of the thin-film hydrogen sensing sensor of Manufacturing Example 1. It can be seen that in the thin-film sample with 20 nm of palladium deposited, the reactivity increases as the hydrogen concentration increases, and it has a broadband detection range for hydrogen concentrations from 0.1% to 1.2%.

[0088] Figure 9 shows the response graph according to hydrogen concentration of the patterned hydrogen sensing sensor of Manufacturing Example 2. It can be seen that in the patterned sample with 10 nm of palladium deposited, the reactivity increases as the hydrogen concentration increases, showing a linear increase in the hydrogen concentration range from 0.1% to 2%. Since the reactivity at the same concentration is similar despite the amount of palladium deposited being less than that of the thin film sample, it can be seen that the patterned sample has superior performance compared to the thin film sample under the same conditions.

[0090] Example 2: Comparison of Reactivity and Resistance of Hydrogen Sensing Sensors by Concentration

[0091] Figure 10 shows a graph of the reaction according to hydrogen concentration based on the thickness of the catalyst layer of the patterned hydrogen sensing sensor of Manufacturing Example 2. It can be seen that when the same pattern is used, the reactivity at high concentrations of hydrogen increases as the thickness of the palladium catalyst layer increases, while the reactivity at low concentrations of hydrogen remains similar.

[0092] Figure 11 shows a graph of the reaction according to hydrogen concentration based on the pattern spacing of the catalyst layer of the patterned hydrogen sensing sensor of Example 2. When palladium of the same thickness is deposited, reactivity increases at both low and high concentrations of hydrogen as the width of the pattern decreases, and through this, it can be seen that hydrogen solubility increases.

[0094] The foregoing description of the present invention is for illustrative purposes only, and those skilled in the art will understand that other specific forms can be easily modified without altering the technical spirit or essential features of the present invention. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. For example, each component described as a single unit may be implemented in a distributed manner, and components described as distributed may likewise be implemented in a combined form.

[0095] The scope of the present invention is defined by the claims set forth below, and all modifications or variations derived from the meaning and scope of the claims and equivalent concepts thereof should be interpreted as being included within the scope of the present invention.

Claims

Claim 1 A method for measuring hydrogen gas comprising: a step of providing a hydrogen detection sensor; a step of introducing a gas containing hydrogen into the hydrogen detection sensor; and a step of measuring hydrogen gas based on a change in the capacitance of the hydrogen detection sensor; wherein the hydrogen detection sensor comprises a doped silicon substrate, an oxide film layer stacked on the doped silicon substrate, a polydimethylsiloxane substrate stacked on the oxide film layer, and a palladium layer stacked on the polydimethylsiloxane substrate. Claim 2 A hydrogen gas measurement method according to claim 1, characterized in that the width of the palladium layer of the hydrogen sensing sensor is 20 μm to 2 cm and the thickness of the palladium layer is 5 to 300 nm. Claim 3 A hydrogen gas measurement method according to claim 1, characterized in that the palladium layer is laminated as a thin film without a pattern. Claim 4 A hydrogen gas measurement method according to claim 1, characterized in that the palladium layer is stacked in a patterned manner having a pattern. Claim 5 A hydrogen gas measurement method according to claim 4, wherein the palladium layer stacked in the patterned form has a thickness of 7.5 to 50 nm and a pattern spacing of 40 to 320 μm. Claim 6 A method for measuring hydrogen gas according to claim 1, characterized in that the doped silicon substrate and the palladium layer are connected as electrodes, and the oxide film layer and the polydimethylsiloxane substrate are connected as dielectrics to measure electrical capacitance. Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 delete Claim 11 A method for measuring hydrogen gas according to claim 1 or 6, characterized in that the doped silicon substrate and the palladium layer are connected by silver paste (Ag paste). Claim 12 A method for measuring hydrogen gas according to claim 1, characterized in that the palladium layer laminated on the polydimethylsiloxane substrate adsorbs hydrogen gas and expands in area. Claim 13 A hydrogen sensing sensor characterized by comprising: a doped silicon substrate; an oxide film layer laminated on the substrate; a polydimethylsiloxane substrate laminated on the oxide film layer; and a palladium layer laminated on the polydimethylsiloxane substrate. Claim 14 A hydrogen sensing sensor according to claim 13, characterized in that the palladium layer is laminated as a thin film without a pattern or as a patterned type having a pattern. Claim 15 delete Claim 16 A hydrogen sensing sensor according to claim 13, characterized in that the doped silicon substrate and the palladium layer are connected as electrodes, and the oxide film layer and the polydimethylsiloxane substrate are connected as dielectrics to measure electrical capacitance. Claim 17 delete

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