KR101618337B1 - a method for fabricating a sensor and a sensor fabricated thereby - Google Patents

Abstract

The present invention relates to a method for producing a sensor having excellent reaction sensitivity and stability using a mesoporous (mesoporous) thin film without using an enzyme, and a sensor manufactured thereby. The present invention relates to a method for producing an alloy thin film comprising the steps of forming an adhesive layer on a substrate, forming an alloy thin film containing two or more elements on the adhesive layer, A fourth step of heat treating the prepared thin film, and a step of fabricating a sensor using the porous thin film including the substrate, the adhesive layer and the porous layer as working electrodes. According to the present invention, it is possible to realize an environmental sensor that is superior in stability and sensitivity as compared with conventional sensors, enables quick measurement, and can immediately confirm measurement results on the spot.

Description

A method of manufacturing a sensor and a sensor fabricated thereby,

The present invention relates to a method of manufacturing a sensor and a sensor manufactured thereby, and more particularly, to a method of manufacturing a sensor using a mesoporous (mesoporous) thin film having excellent reaction sensitivity and stability, And more particularly to a method for producing a sensor having excellent reaction sensitivity and stability using a mesoporous thin film without using an enzyme and a sensor manufactured thereby.

A sensor is a means for measuring the presence or concentration of a substance to be detected by biologically or chemically reacting a substance to be detected and measuring a change in a signal externally caused by the reaction. Typical sensors include a gas sensor that detects the amount of gas contained in the air, an environmental sensor that measures the concentration of various harmful substances in the solution, or a biosensor that measures the concentration of a substance contained in the sample from the biological chemical reaction of the biochemical material have.

Especially, measurement devices such as GC (Gas Chromatography) or HPLC (High Performance Liquid Chromatography), which are generally used to detect harmful substances in the environment field, are expensive equipment, complex operation and long measuring time. Also, since it is difficult to carry the equipment, it is troublesome to collect the sample and bring it to the laboratory for analysis.

On the other hand, there are some devices that are miniaturized to be portable, but the sensors of such devices generally have immobilized enzymes that react with specific substances. In such enzyme sensors, there is a large variation in sensitivity depending on the individual sensors, The enzyme is easily deteriorated according to the environmental conditions such as temperature and humidity, and there is a problem in the quality control of the product.

As a sensor that does not use an enzyme, there have been a lot of researches on a non-small-scale environmental sensor that detects a biochemical substance using a noble metal (Pt, Au, etc.) electrode. Some environmental pollutants are adsorbed on the electrode surface of the sensor and become polymerized, or the reaction material does not fall off from the surface of the sensor and is covered, thereby paralyzing the function of the sensor. Therefore, the measurement itself may be required under a strong acidic condition with low pH.

1. Korean Patent Publication No. 10-2012-0016436 (Feb. 24, 2012) 2. KOKAI Publication No. 2003-0089115 (November 21, 2003)

The present invention relates to a method of manufacturing a sensor including a nanoporous (mesoporous) thin film, and a method of manufacturing a sensor having excellent stability and response sensitivity without using an enzyme and a sensor ≪ / RTI >

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, including: a first step of forming an adhesive layer on a substrate; a second step of forming an alloy thin film containing two or more elements on the adhesive layer; A fourth step of forming a porous layer by heat treating the prepared thin film or applying an oxide on the thin film, and a fifth step of forming a sensor using the porous thin film including the substrate, the adhesive layer and the porous layer as working electrodes, The method of manufacturing a sensor according to claim 1,

Another aspect of the present invention includes a working electrode and a reference electrode, wherein the working electrode comprises a substrate, an adhesive layer formed on the substrate, and a porous layer formed on the adhesive layer Sensor.

According to the present invention, it is possible to produce a sensor having excellent sensitivity and stability by a relatively simple process, and further, to realize a sensorless environment sensor having excellent sensitivity and stability against environmentally harmful substances without using an enzyme under neutral conditions, Compared with conventional environmental sensors, environmental pollutants can be measured quickly in the field.

1 is a schematic view schematically showing the structure of a sensor according to the present invention.
2 is a schematic view showing the structure of a working electrode according to the present invention (A: before selective etching, and B: after selective etching).
3 is a flow chart of a manufacturing process of a sensor according to the present invention.
Figure 4 is a photograph of a thin film (A: dealloying before surface, B: dealloying after surface, C: dealloying after cross section).
5 is a graph showing a change in current while adding phenol to the sensor according to Example 1. Fig.
FIG. 6 is a graph showing the change in current while adding phenol to the sensor according to Example 2. FIG.
FIG. 7 is a graph showing the change in current while adding phenol to the sensor according to Example 3. FIG.
FIG. 8 is a graph showing changes in sensitivity of a sensor during repetitive measurement of phenol with respect to the sensors according to Examples 1 to 3. FIG.
FIG. 9 is a graph showing changes in current while adding hydroxyamine to the sensor according to Example 1. FIG.
FIG. 10 is a graph showing the change in current while adding aniline to the sensor according to Example 1. FIG.
11 is a voltammetry measurement result of the sensor according to Example 1 and Comparative Example.

Preferred embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments of the present invention can be modified in various ways, and the scope of the present invention is not limited to the embodiments described below.

The present invention relates to a method for manufacturing an environmental sensor having excellent stability and sensitivity by using a porous thin film (50), particularly a mesoporous thin film having a size of 1 nm to 50 nm as an operating electrode.

FIG. 1 schematically shows the structure of a sensor according to the present invention. FIG. 2 (a) shows the cross-sectional structure of the working electrode before the selective etching, and FIG. 2 (b) shows the cross-sectional structure of the working electrode after the selective etching. 1 shows a three-electrode system sensor having a working electrode 1, an auxiliary electrode 2 and a reference electrode 3, but is not limited to a three-electrode system including a working electrode, And may be a two-electrode system sensor including only an auxiliary electrode.

The porous thin film 50 constituting the working electrode includes a substrate 10, an adhesive layer 20 formed on the substrate 10, an underlayer 30 formed on the adhesive layer 20, And a porous layer 41 formed on the substrate 30.

As the substrate 10, any substrate having a flat surface can be used, and preferably at least one of ceramic, alumina, silicon wafer, silicon oxide, quartz, glass, and mica can be selected and used. Preferably, at least one selected from the group consisting of silicon wafers and mica is used. The silicon wafer 100 means the (100) plane of the silicon crystal structure.

The porous layer 41 can be formed by forming an alloy thin film 40 containing two or more elements, and then selectively removing specific elements. The alloy thin film 40 may preferably include at least one element selected from the group consisting of Si, Pt, Pd, Au and Ag. More preferably, Si, and may further include at least one element selected from the group consisting of Pt, Pd, Au and Ag. Specifically, for example, the alloy thin film 40 may be formed of a binary alloy such as Si-Pt, Si-Pd, Si-Au, Si-Ag, Si-Pt-Pd, Si- Pt-Pd-Au, Si-Pd-Ag, and Si-Au-Ag, Si-Pt-Pd-Au and Si- -Au-Ag, or the like. A porous layer can be formed by selectively removing a specific element from the alloy thin film 40. Most preferably, the porous layer 41 composed of the remaining components can be obtained by selectively removing Si. The porous layer 41 may have a pore size of 1 to 50 nm. The porous layer 41 may have a thickness of 1 nm to 500 nm. If the thickness is less than 1 nm, it is impossible to cause a reaction sufficient to detect the detection substance. If the thickness exceeds 500 nm, the waste and the unit price of the material are increased more than necessary. Which may result in degraded performance. It may also have a roughness factor of 1 to 500. It is also a main feature of the present invention that the porous layer 41 produced by selectively removing a specific element from the alloy thin film 40 is employed as a working electrode or an auxiliary electrode of the environmental sensor. Therefore, the electrode surface of the sensor itself can be made nano-structured to have reactivity with respect to the chemical substance, so that it is not necessary to fix the enzyme on the electrode surface of the sensor. Further, without the help of the enzyme, The substance concentration can be measured.

The under layer 30 functions to prevent the etching process from being excessively advanced to etch the substrate 10. The underlayer 30 may also be referred to as an etch-stop layer. If there is no problem of overetching, the underlayer 30 is an optional construction that does not need to be formed. The underlayer material 30 may be any material that has resistance to etching and can stop the etching process. Preferably, the underlayer material 30 may be selected from the group consisting of Au, Pt, and Pd, More preferably, at least one selected from the group consisting of Au and Pt can be used.

The adhesive layer 20 increases the adhesion between the underlayer 30 and the substrate 10 or the adhesion between the porous layer 41 and the substrate 10, thereby enabling to more effectively transmit an electrical signal. As the material of the adhesive layer 20, any material having good adhesion to both the substrate and the under layer can be used. Preferably, one or more materials selected from the group consisting of Ti, Mo, Ni and Cr can be used. Preferably, Ti can be used.

A metal oxide layer may further be formed on the porous layer 41. By further forming a metal oxide layer, the stability of the sensor can be improved. As the material of the metal oxide layer, any material capable of transferring electric charges to and from the contacted material can be used. Preferably, the metal oxide layer is made of titania, alumina, seria, zirconia, Zinc oxide, zinc oxide, zinc oxide, and zinc oxide. More preferably, one or more selected from the group consisting of titania, ceria, and zirconia may be used.

The sensor according to the present invention can be used, for example, to detect the concentration of a compound containing a phenyl group (for example, phenol) or a compound containing an amine group (for example, hydroxylamine, aniline).

The sensor according to the present invention can be manufactured as follows. FIG. 3 shows a manufacturing process of the sensor according to the present invention. The following description will be given.

First, an adhesive layer may be formed on a substrate (S1). As the substrate 10, any substrate having a flat surface can be used, and preferably at least one of ceramic, alumina, silicon wafer, silicon oxide, quartz, glass, and mica can be selected and used. Preferably, at least one selected from the group consisting of silicon wafers and mica is used. The adhesive layer may be formed by a deposition method generally used in this technical field, for example, a sputtering method, a plasma deposition method, a thermal evaporation method, or the like. As the material of the adhesive layer 20, any material having good adhesion to both the substrate and the under layer can be used, and preferably one or more materials selected from the group consisting of Ti, Mo, Ni and Cr can be used. Preferably, Ti can be used.

Next, an underlayer can be formed on the adhesive layer (S2). The under layer may be formed by a deposition method generally used in this technical field, for example, a sputtering method, a plasma deposition method, a thermal evaporation method, or the like. The underlayer material 30 may be any material capable of stopping the etching due to etching resistance. Preferably, the underlayer material 30 may be selected from the group consisting of Au, Pt, and Pd, More preferably, at least one selected from the group consisting of Au and Pt can be used, and Pt is most preferably used.

Next, an alloy thin film containing two or more elements on the under layer can be formed (S3). The alloy thin film can be generally formed by a deposition method used in this technical field. For example, an alloy thin film can be formed by a method such as a sputtering method, a plasma deposition method, a thermal evaporation method or the like, and most preferably, a sputtering method Is preferably used. Sputtering is a simple process and has a low possibility of discharging environmental pollutants. Also, the deposition rate of the deposited elements can be easily controlled. Further, it is easy to control the porosity in the process of selectively removing specific elements in the future, and further, the porosity can be kept constant. For example, two or more elements may be sputter deposited to form a thin film containing two or more elements. Specifically, a thin film may be deposited by sputtering a target containing two or more elements at the same time, A plurality of targets including elements may be mounted and then sputtered to form an alloy thin film. The alloy thin film 40 may preferably include at least one element selected from the group consisting of Si, Pt, Pd, Au and Ag. More preferably, Si, and may further include at least one element selected from the group consisting of Pt, Pd, Au and Ag. For example, the thin film may be made of Si-Pt, Si-Pd, Si-Au, a binary alloy of Si-Ag, Si-Pt-Pd, Si- Pt-Pd-Au, Si-Pd-Ag, Si-Au-Ag ternary alloy, Si-Pt-Pd-Au and Si- It may be an oxide-based alloy. In the process of depositing two or more elements, the volume ratio between the elements can be controlled. The porosity of the porous layer can be adjusted according to the volume ratio of the dissolved elements. Preferably, Si is preferably 20 to 95% by volume, and most preferably, Si is 30 to 80% by volume. If the content of Si is less than 20 vol%, it is difficult to form a sufficient porous structure after etching, while if it exceeds 95 vol%, it is difficult to maintain the porous structure after etching.

Next, a specific element may be selectively removed from the alloy thin film to form a porous layer (S4). The particular element that is selectively removed is most preferably Si. When a specific element is removed, an empty space, that is, a pore is formed in the portion. Removal of specific elements is continuous from the surface toward the interior, and for this reason, pores connected in series can be formed. As a specific example, the pores may have a columnar shape (see Fig. 4 (c)). The etch proceeds from the surface side of the alloy thin film toward the substrate and then stops at the underlayer.

As a method for selectively removing a specific element, a general method in the technical field can be used, and preferably, selective dealloying or selective dry etching can be used.

The selective dissolution method is a method of forming a porous structure by selectively removing a highly reactive metal element with an etching solution in an alloy thin film of two or more metals. Solvents that are selectively soluble in certain elements may be used to selectively remove certain elements. As the solvent, it may be different depending on the element to be removed. For example, when removing Si, HF may be used. In order to remove a specific element from the alloy thin film, a cell is constituted of an alloy thin film as a working electrode, an electrochemical cell is constituted by using a solvent as an electrolyte, and a certain voltage is applied for a predetermined time by a potentiostat, Can be dissolved and removed. At this time, the dissolution amount of a specific element can be controlled according to the concentration of the solvent, the applied voltage and the time. Preferably, a voltage in the range of 0.9 to 1.1 V is applied and the constant-voltage method can be performed for 0.5 to 20 minutes. As another method, a method of applying voltage while raising and lowering the voltage at a rate of about 10 mV / s in the range of 0 V to 1.3 V may be used. By dissolving some or all of the specific elements in this way, a porous layer made of the remaining elements can be produced.

The selective dry etching method is a method of selectively removing a specific element by using a gas having reactivity with a specific gas without using an etching solution. For example, Si elements in a thin film can be removed by using XeF ₂ gas.

In the case of the thus-formed porous layer, it is preferable that the pore size is adjusted to 1 to 50 nm. This range of pores is called "mesoporous". The roughness factor is preferably 1 to 500. "Roughness" is defined as the ratio of the actual surface area of the thin film per unit area of the geometric unit. For example, if the actual surface area is measured for an area of 1 cm width and 40 cm ² , the roughness is 40. The roughness of a metal nanostructure can be calculated mainly by adsorption / desorption of hydrogen atoms in the metal nanostructure by a cyclotron voltmeter (CV) in an electrochemical device. The reason why the pore size and the roughness should be limited to the above range is that if the pore is too small, the substance molecules are difficult to enter into the pores to be detected, whereas when the pores are too large, the porous structure itself becomes too weak and the actual surface area of the film is reduced to be.

Next, a step of heat-treating the thin film having the substrate, the adhesive layer, the under layer (optional), and the porous layer may be further performed (S5). The stability of the sensor can be improved by heat treatment. The existing sensor has a problem that the sensor sensitivity drops rapidly after 1 or 2 times measurement. In the embodiment in which the sensor according to the present invention is evaluated by heat treatment, the sensor of the present invention maintains the sensitivity of the sensor up to 5 times. The heat treatment can be carried out at 50 to 250 ° C for 10 minutes to 3 hours. If the temperature is lower than the above range or the time is shorter, there is no heat treatment effect. If the temperature is higher than the above range or the time is longer, the structure of the thin film itself may be deformed and the function as a sensor may be lost. The present process can be selectively performed as needed, but if the stability of the sensor is to be improved, the present process can be performed.

Next, a step of forming a metal oxide layer on the porous layer may be further performed (S5). The stability of the sensor can be improved by forming the metal oxide layer on the porous layer. This step can be carried out selectively as required. That is, when the stability of the sensor is sufficient, the present step need not be performed. In the case where the stability of the sensor is to be improved, the present step can be performed. The metal oxide layer may be deposited using a deposition method commonly used in the art, and may preferably be formed by atomic layer deposition, sputtering, or impregnation. As the material of the metal oxide layer, any material can be used as long as it is capable of transferring electric charges to the contacted material. Preferably, one or more materials selected from the group consisting of titania, alumina, ceria, zirconia and zinc oxide can be used And more preferably at least one selected from the group consisting of titania, ceria and zirconia. The metal oxide layer increases the stability of repeated measurement of the sensor. The present invention can compensate for the disadvantage that the sensor sensitivity drops sharply after one or two measurements of the conventional sensor. According to the embodiment of the present invention, It was also possible to maintain the sensitivity to the sieve.

Next, the sensor can be constituted by using the thin film including the substrate, the adhesive layer and the porous layer, or the substrate, the adhesive layer, the under layer and the porous layer as working electrodes (S6). As the reference electrode, an electrode material generally used in a sensor can be used. Preferably, Ag / AgCl can be used. As a counter electrode, an electrode material generally used in a sensor can be used. Can be used. The sensor may be a two-electrode system or a three-electrode system. The two-electrode system sensor includes a working electrode and a reference electrode. The three-electrode system sensor includes a working electrode, a reference electrode, .

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. It is to be understood that the present invention is not limited thereto.

First, Ti was sputter deposited on the surface of an n-doped Si (100) wafer (1 cm x 2 cm) to form a Ti adhesive layer having a thickness of 3 nm. Next, Au was sputter deposited to form an underlayer of 30 nm. Next, the Au target and the Si target were mounted together and then simultaneously sputter-deposited to form a 150 nm Au-Si alloy thin film (10 W for the Au target and 200 W for the Si target). As a result of AES analysis (PHI-700, Ulvac-PHI), the content of Si in the Au-Si alloy thin film was 55 atomic%. Next, the porous thin film was prepared by selectively removing Si from the alloy thin film by using an aqueous solution of HF (dealloying).

Here, an electrochemical cell (CH660, CH Instrument Inc.) comprising Ag / AgCl (3M KCl) as a reference electrode, a Pt wire as a counter electrode, the porous thin film as a working electrode, and a 3% HF aqueous solution as an electrolyte Thereafter, a voltage of 1.0 V was applied through a potentiostat to selectively remove Si from the Au-Si alloy thin film to produce a porous Au thin film. The Si substrate was used after sealing with a silicone adhesive in advance. Fig. 4 shows photographs of the fabricated films (A: surface photograph of the dealloying film, B: surface photograph of the dealloying film, and C: cross section of the film after dealloying). Referring to FIG. 4, it can be seen that the Au remaining after removing Si from the Au-Si alloy thin film forms a mesoporous porous thin film having pores of several tens of nm. The residual amount of Si is about 0 ~ 5 atomic%, and most of Si is removed. In addition, the roughness factor of the porous Au thin film was measured to be 25.

Next, we fabricated the same electrochemical cell using the fabricated porous Au thin film to fabricate the environmental sensor.

A sensor was fabricated in the same manner as in Example 1 except that a titania layer (ALD 5 cycle) was formed on the porous Au thin film of Example 1 by the ALD method.

A sensor was fabricated in the same manner as in Example 1, except that the porous Au thin film of Example 1 was heat-treated at 100 ° C for 1 hour in a nitrogen atmosphere.

[Comparative Example]

A sensor was fabricated in the same manner as in Example 1 except that flat Au having a thickness of 150 nm manufactured by sputtering an Au target was used as the working electrode.

[Sensor performance evaluation]

1. Sensor performance evaluation for phenol

1-1. Evaluation of the performance of the sensor according to Embodiment 1

The current change was measured by adding various concentrations of phenol to a neutral (pH = 7.2) PBS (phosphate-buffered saline) buffer solution at room temperature while applying a voltage of 0.7 V to the reference electrode. 5. Before this test, the porous thin film was cleaned by scanning a voltage of -0.25 V to 1.8 V against Ag / AgCl (3M KCl) at a rate of 100 mV / s in 1.5 MH ₂ SO ₄ solution. Referring to FIG. 5, it can be seen that stabilization of a constant current value is stabilized within several tens of seconds immediately after the addition of phenol, and that the sensor has a constant value. From this, it can be seen that the electrode reaction is stabilized within a few tens of seconds Can be confirmed. That is, in the sensor according to the present invention, the reaction rate is fast enough to detect phenol immediately in the field. In addition, it can be confirmed that the current increases almost linearly as the concentration of phenol increases. The lowest detectable phenol concentration was 1 [mu] M. The sensitivity of the sensor was about 170 nA cm ^-2 μM ^-1 up to 200 μM. However, once the sensor was used, it was repeatedly measured with a certain amount of phenol. The results are shown in Fig. Referring to FIG. 8, it can be seen that the reaction sensitivity dropped sharply beyond about 5 times.

1-2. Evaluation of the performance of the sensor according to the second embodiment

The performance of the sensor was measured in the same manner as in Example 1, and the results are shown in FIG. Referring to FIG. 6, stabilization of a constant current value was stabilized within several tens of seconds immediately after the addition of phenol, which is similar to the previous case. In addition, the current linearly increased as the phenol concentration increased from 1 μM to 200 μM. The lowest detectable phenol concentration was 1 μM. The sensitivity of the sensor was about 175 nA cm ^-2 μM ^-1 , similar to the comparative example without the titania layer. FIG. 8 shows the result of repeated measurement up to 8 times. Referring to FIG. 8, although the sensitivity of the reaction was somewhat reduced, the rate of decrease was smaller than that of Example 1 in which there was no titania layer.

1-3. Evaluation of the performance of the sensor according to the third embodiment

The performance of the sensor was measured in the same manner as in Example 2, and the results are shown in FIG. Referring to FIG. 7, it was similar to the previous case such that stabilization of a constant current value was stabilized within tens of seconds immediately after the addition of phenol. In addition, the current linearly increased as the phenol concentration increased from 1 μM to 200 μM. The lowest detectable phenol concentration was 1 μM. The sensitivity of the sensor was about 175 nA cm ^-2 μM ^-1 , similar to that of Example 1 without heat treatment. FIG. 8 shows the result of repeated measurement up to 9 times. Referring to FIG. 8, the sensitivity of the reaction was somewhat reduced, but the degree of decrease was less than that of the porous Au film (Example 1) without any treatment.

2. Sensor performance evaluation for hydroxylamine

A porous Au thin film was prepared in the same manner as in Example 1. The same electrochemical cell as in Example 1 was constructed to measure the concentration of hydroxylamine, which is a typical environmental pollutant including amino group (NH ₂ ), using the prepared porous Au thin film. Then, the current change was measured while various concentrations of hydroxylamine were added to a neutral (pH = 7.2) PBS buffer with a voltage of 0.3 V compared to the reference electrode, and the results are shown in FIG. According to FIG. 9, it can be seen that the hydroxylamine is stabilized within several tens of seconds immediately after the addition of hydroxylamine, stabilizing a constant current value and having a constant value. From this, it can be seen that, in the case of the sensor according to the present invention, Can be confirmed. That is, in the sensor according to the present invention, the reaction rate is fast enough to detect the hydroxylamine immediately in the field. It can be seen that the current increases almost linearly as the aniline concentration increases from 0.5 μM to 2700 μM. In particular, the sensitivity of the reaction was about 200 nAcm ^-2 μM ^{-1 up} to 14 μM and about 150 nA cm ^-2 μM ^-1 14 μM to 2700 μM. The lowest detectable concentration was 0.5 μM.

3. Sensor performance evaluation for aniline

3-1. Evaluation of the performance of the sensor according to Embodiment 1

A porous Au thin film was prepared in the same manner as in Example 1. The same electrochemical cell as in Example 1 was constructed for measuring the concentration of aniline, which is a typical environmental pollutant containing amino group (NH ₂ ), using the prepared porous Au thin film. Then, the current change was measured while adding various concentrations of aniline to the neutral (pH = 7.2) PBS buffer with a voltage of 0.8 V relative to the reference electrode. The results are shown in Fig. 10, it can be seen that the electrode reaction immediately after the addition of aniline stabilized within several tens of seconds and had a constant current value. That is, the reaction rate was fast enough to detect aniline directly in situ. As the aniline concentration increases from 0.5 μM to 30 μM, the current increases almost linearly. In particular, the sensitivity of the reaction was about 350 nA cm ^-2 μM ^-1 up to the concentration of 30 μM. The lowest detectable concentration was 0.5 μM.

3-2. Performance evaluation of the sensor according to the comparative example

For the sensor according to the comparative example, the cyclic voltammetry was measured in a solution of neutral (pH = 7.2) PBS buffer and 1.6 mM aniline, and the results are shown in FIG. 11, And the performance results for the aniline of the corresponding sensor. 11, it can be seen that the amount of current drawn from the porous Au film indicated by the red line is much larger than the amount of current from the flat Au film indicated by the black line. That is, it can be seen that the porous Au thin film is more reactive than the flat Au thin film.

The terms used in the present invention are intended to illustrate specific embodiments and are not intended to limit the invention. The singular presentation should be understood to include plural meanings, unless the context clearly indicates otherwise. Or " an embodiment " means that there is a feature, a number, a step, an operation, an element, or a combination thereof described in the specification, and does not exclude it. The present invention is not limited by the above-described embodiment and the accompanying drawings, but is intended to be limited by the appended claims. Therefore, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. I will say.

1: working electrode 2: counter electrode
3: reference electrode V: voltmeter
A: ammeter 10: substrate
20: an adhesive layer 30: an underlayer,
40: alloy thin film (before etching) 41: porous layer (after etching)
50: Porous thin film

Claims (20)

A substrate;
A first step of forming an adhesive layer on the substrate;
A second step of forming an alloy thin film containing two or more elements on the adhesive layer;
A third step of selectively removing a specific element from the alloy thin film to form a porous layer;
A fourth step of heat-treating the thin film; And
And a fifth step of fabricating the sensor using the porous thin film including the substrate, the adhesive layer, and the porous layer as working electrodes. The method of claim 1, further comprising forming an underlayer between the adhesive layer and the alloy thin film. The method of manufacturing a sensor according to claim 1, wherein the alloy thin film is formed by sputtering two or more elements. The method of manufacturing a sensor according to claim 1, wherein the alloy thin film comprises Si and at least one element selected from the group consisting of Pt, Pd, Au and Ag. The method according to claim 1, wherein in the third step, a porous layer is formed by selectively removing a specific element using a solvent having selective solubility for a specific element. The method of manufacturing a sensor according to claim 1, wherein in the third step, the porous layer is formed by selectively removing the specific element dry using a reactive gas highly reactive with the specific element. 5. The method of claim 4, wherein the specific element removed from the alloy thin film is Si. The method of claim 1, further comprising forming a metal oxide layer on the porous layer. 9. The method of claim 8, wherein the metal oxide layer is formed by a method selected from an atomic layer deposition method, a sputtering method, and an impregnation method. [9] The method of claim 8, wherein the metal oxide layer comprises at least one selected from the group consisting of titania, ceria, zirconia, alumina, and zinc oxide Of the sensor. The method of claim 1, wherein the heat treatment is performed at 50 to 250 ° C for 10 minutes to 3 hours. The method of claim 1, wherein the porous layer has pores of 1 to 50 nm in size. The method of claim 1, wherein the porous layer has a thickness of 1 nm to 500 nm. The method according to claim 1, wherein the porous layer has a roughness factor of 1 to 500. Board;
An adhesive layer formed on the substrate;
A porous layer formed on the adhesive layer; And
And a metal oxide layer formed on the porous layer as a working electrode. 16. The sensor of claim 15, further comprising an underlayer between the adhesive layer and the porous layer. 16. The sensor of claim 15, wherein the sensor is used to detect at least one concentration selected from the group consisting of a compound comprising a phenyl group and a compound comprising an amine group. The sensor according to claim 17, wherein the compound containing phenyl group comprises phenol, and the compound containing amine group comprises at least one member selected from the group consisting of hydroxylamine and aniline. delete 16. The method according to claim 15, wherein the metal oxide layer comprises at least one selected from the group consisting of titania, ceria, zirconia, alumina, and zinc oxide The sensor features.

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