Thin-film detector based on transistor-to-diode configuration and its fabrication method

Abstract

This invention provides a thin-film detector based on a transistor-to-diode configuration and its fabrication method, comprising: a first substrate layer; a second substrate layer; a thin film layer; a source electrode; a drain electrode; a dielectric layer; and a gate electrode. The second substrate layer is disposed above the first substrate layer; the thin film layer is disposed above the second substrate layer; the source electrode and drain electrode are disposed above the thin film layer, forming Schottky or ohmic contacts with the thin film layer; a conductive channel is formed in the thin film layer between the source electrode and drain electrode; the dielectric layer is disposed above the source electrode, the conductive channel, and the drain electrode; and the gate electrode is disposed above the dielectric layer and the source electrode, with the gate electrode and source electrode being electrically connected. Based on the photodetector structure provided by this invention, a fixed Schottky barrier is formed between the source electrode and the thin film layer, effectively suppressing dark current, while also possessing rectification characteristics similar to a diode, greatly improving photodetector performance and stability.

Description

Technical Field

[0001] This invention relates to the field of optoelectronic technology, and in particular to a thin-film detector based on a transistor configured as a diode and its fabrication method. Background Technology

[0002] With the development of photonics, its applications are becoming increasingly widespread, such as lidar, gyroscopes, biosensors, and spectrometers. Thin film materials, which have been developed in recent years, have proven to have enormous application potential in circuits and optoelectronics due to their excellent optical and electrical properties.

[0003] In the existing technology, most photodetectors based on thin film materials are two-terminal device structures based on PN junctions and Schottky barriers. Although they have advantages such as high responsivity and fast speed, they are generally limited by the semiconductor properties of the materials and have problems such as large dark current and low detectivity. Summary of the Invention

[0004] In view of this, embodiments of the present invention provide a thin-film detector based on a transistor configured as a diode and a method for its fabrication, in order to eliminate or improve one or more defects existing in the prior art, and solve the problems of large dark current and low detectivity in existing photodetectors.

[0005] On one hand, the present invention provides a thin-film detector based on a transistor configured as a diode, characterized in that it comprises:

[0006] First substrate layer;

[0007] A second substrate layer is disposed above the first substrate layer, and the second substrate layer is made of an insulating material;

[0008] A thin film layer disposed above the second substrate layer;

[0009] A source electrode and a drain electrode are disposed above the thin film layer and respectively form a Schottky contact or an ohmic contact with the thin film layer; a conductive channel is formed in the thin film layer between the source electrode and the drain electrode;

[0010] A dielectric layer is disposed above the source electrode, the conductive channel, and the drain electrode;

[0011] A gate electrode is disposed above the dielectric layer and the source electrode, and the gate electrode and the source electrode are connected.

[0012] In some embodiments of the present invention, the substrate material of the first substrate layer is silicon; the substrate material of the second substrate layer is silicon dioxide.

[0013] In some embodiments of the present invention, the thin film material of the thin film layer is selected as a two-dimensional material or a semiconductor thin film material.

[0014] In some embodiments of the present invention, the thin film material of the thin film layer is selected as carbon nanotubes.

[0015] In some embodiments of the present invention, the gate electrode is made of indium tin oxide.

[0016] This invention also provides a method for fabricating a thin-film detector based on a transistor-diode configuration, characterized in that the method is used to fabricate the thin-film detector based on a transistor-diode configuration as described above, and the method includes the following steps:

[0017] Obtain the first substrate layer;

[0018] A second substrate layer is grown on the first substrate layer;

[0019] A thin film layer is obtained by depositing a predetermined semiconductor material onto the second substrate layer using a predetermined deposition method.

[0020] Preset regions for the source electrode and the drain electrode are exposed on the thin film layer using electron beam lithography. A first preset metal material is deposited on the preset regions for the source electrode and the drain electrode using electron beam evaporation to obtain the source electrode and the drain electrode. The source electrode and the drain electrode respectively achieve Schottky contact with the thin film layer. A conductive channel is formed in the portion of the thin film layer between the source electrode and the drain electrode.

[0021] A predetermined region of the dielectric layer is exposed on the source electrode, the drain electrode, and the conductive channel using an electron beam lithography method. A predetermined insulating material is deposited on the predetermined region of the dielectric layer using an atomic layer deposition method, or a metal with a nanometer-thickness is deposited on the predetermined region of the dielectric layer and then subjected to high-temperature oxidation to obtain the dielectric layer; and the dielectric layer is used as the gate dielectric of the transistor.

[0022] A predetermined region of the gate electrode is exposed on the dielectric layer and the source electrode using an electron beam lithography method. A second predetermined metal material is deposited on the predetermined region of the gate electrode using an electron beam evaporation method to obtain the gate electrode. The gate electrode and the source electrode are then connected.

[0023] In some embodiments of the present invention, a preset semiconductor material is deposited on the second substrate layer using a preset deposition method to obtain a thin film layer. The preset semiconductor material is selected as carbon nanotubes, and the preset deposition method is electrophoretic deposition, dry transfer, or wet transfer.

[0024] In some embodiments of the present invention, the first preset metal material includes at least one or more combinations of palladium, titanium and gold; the second preset metal material is indium tin oxide.

[0025] In some embodiments of the present invention, a predetermined region of the dielectric layer partially covers the source electrode, and the gate electrode is directly grown on the surface of the portion of the source electrode not covered and a portion of the conductive channel region.

[0026] The beneficial effects of the present invention are at least as follows:

[0027] This invention provides a thin-film detector based on a transistor-to-diode configuration and its fabrication method, comprising: growing a source electrode and a drain electrode on a semiconductor thin film layer, wherein the source electrode and the drain electrode respectively form a Schottky contact or an ohmic contact with the thin film layer; growing a gate electrode on the source electrode and a gate dielectric, wherein the source electrode and the gate electrode are short-circuited to form a diode-like structure; and through the joint control of the gate electrode and the source electrode, a Schottky barrier of fixed height is formed between the source electrode and the thin film layer, effectively suppressing carrier migration and thus suppressing dark current; at the same time, it has rectification characteristics similar to a diode, greatly improving photoelectric detection performance and stability.

[0028] Furthermore, the thin film layer has the characteristic of being easily tunable. In the fabrication method of thin film detector based on transistor-to-diode mode, the width of the Schottky barrier between the source electrode and the thin film layer can be effectively controlled by adjusting the thickness of the gate dielectric; the height of the Schottky barrier between the source electrode and the thin film layer can be effectively controlled by adjusting the material of the gate electrode, thereby meeting specific needs and / or specific application scenarios, and having universal applicability.

[0029] Additional advantages, objects, and features of the invention will be set forth in part in the description which follows, and will also become apparent in part to those skilled in the art upon studying the description, or may be learned by practice of the invention. The objects and other advantages of the invention can be realized and obtained by means of the structures specifically pointed out in the specification and drawings.

[0030] Those skilled in the art will understand that the objectives and advantages achievable with the present invention are not limited to those specifically described above, and that the above and other objectives achievable with the present invention will become clearer from the following detailed description. Attached Figure Description

[0031] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, are not intended to limit the invention. In the drawings:

[0032] Figure 1 This is a schematic diagram of a thin-film detector based on a transistor connected in diode mode according to an embodiment of the present invention.

[0033] Figure 2 This is a schematic diagram of the energy band of a thin-film detector based on a transistor connected in diode mode in one embodiment of the present invention under different states.

[0034] Figure 3 This is a schematic diagram illustrating the steps of a method for fabricating a thin-film detector based on a transistor connected in diode mode according to an embodiment of the present invention. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments and accompanying drawings. Here, the illustrative embodiments and descriptions of this invention are used to explain the invention, but are not intended to limit the invention.

[0036] It should also be noted that, in order to avoid obscuring the invention with unnecessary details, only the structures and / or processing steps closely related to the solution according to the invention are shown in the accompanying drawings, while other details that are not closely related to the invention are omitted.

[0037] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, element, step, or component, but does not exclude the presence or addition of one or more other features, elements, steps, or components.

[0038] It should also be noted that, unless otherwise specified, the term "connection" in this article can refer not only to a direct connection, but also to an indirect connection involving an intermediary.

[0039] In the following description, embodiments of the invention will be illustrated with reference to the accompanying drawings. In the drawings, the same reference numerals represent the same or similar parts, or the same or similar steps.

[0040] It should be emphasized here that the step markers mentioned below are not a limitation on the order of the steps, but should be understood as meaning that the steps can be executed in the order mentioned in the embodiments, or in a different order than in the embodiments, or several steps can be executed simultaneously.

[0041] To address the problems of large dark current and low detectivity in existing photodetectors, this invention provides a thin-film detector based on a transistor configured as a diode, comprising:

[0042] First substrate layer.

[0043] The second substrate layer is disposed above the first substrate layer and is made of an insulating material.

[0044] Thin film layer; the thin film layer is disposed above the second substrate layer.

[0045] Source electrode and drain electrode; the source electrode and drain electrode are disposed above the thin film layer and respectively achieve Schottky contact or ohmic contact with the thin film layer; a conductive channel is formed in the thin film layer between the source electrode and drain electrode.

[0046] Dielectric layer; the dielectric layer is disposed above the source electrode, conductive channel and drain electrode.

[0047] Gate electrode; The gate electrode is positioned above the dielectric layer and the source electrode, and the gate electrode and the source electrode are connected.

[0048] Specifically, such as Figure 1 As shown, the thin-film detector includes: a first substrate layer 1; a second substrate layer 2; a thin film layer 3; a source electrode and a drain electrode 4; a dielectric layer 5; and a gate electrode 6. The source electrode and drain electrode are both labeled 4. Figure 1 In the diagram, the electrode closer to the left is the drain electrode, and the electrode closer to the right, which is connected to the gate electrode, is the source electrode.

[0049] In some embodiments, the substrate material of the first substrate layer is silicon; the substrate material of the second substrate layer is silicon dioxide.

[0050] In some embodiments, the second substrate layer is formed by thermal oxidation of the silicon substrate of the first substrate layer to produce silicon dioxide.

[0051] Silicon is the foundation of the integrated circuit industry, accounting for 98% of semiconductor materials. Silicon substrates are currently the cheapest, largest available, and most mature semiconductor material for device fabrication. Semiconductors are produced using thin-film technology, which involves growing epitaxial layers on silicon substrates and fabricating devices within those layers. Choosing silicon substrates ensures that the direction of the grown epitaxial layer aligns with the substrate, thereby guaranteeing the density and stability of the structure.

[0052] The thin film material for the thin film layer is either a two-dimensional material or a semiconductor thin film material.

[0053] In some embodiments, carbon nanotubes are selected as the thin film material. A carbon nanotube thin film is a two-dimensional carbon nanotube network structure formed by filling a freely arranged array of carbon nanotubes using a specific method. Carbon nanotube thin films are flexible, transparent, conductive, and chemically stable.

[0054] Metal electrodes are deposited on the surface of the thin film layer to serve as the source and drain electrodes of the transistor. In some embodiments, the source and drain electrodes are made of metals such as palladium, titanium, or gold. A conductive channel is formed between the source and drain electrodes in the semiconductor thin film layer.

[0055] The source and drain electrodes form Schottky or ohmic contacts with the thin film layer, creating a Schottky barrier. A Schottky contact occurs when a metal and semiconductor material come into contact, causing the energy bands of the semiconductor to bend at the interface, thus forming a Schottky barrier. An ohmic contact also forms a barrier layer when a semiconductor and metal come into contact; however, when the semiconductor doping concentration is very high, electrons can tunnel through the barrier.

[0056] A dielectric layer is grown above the source electrode, drain electrode, and conductive channel to serve as the gate dielectric of the transistor. The gate dielectric is disposed below the gate electrode to isolate the gate electrode and the conductive channel. In some embodiments, the gate dielectric is made of an oxide material such as hafnium oxide or yttrium oxide.

[0057] In existing technologies, silicon dioxide is commonly used as the gate dielectric material. As transistor dimensions shrink, the silicon dioxide dielectric must become increasingly thinner, leading to a series of problems such as leakage current and deteriorated gate control. For example, the leakage current increases dramatically with decreasing silicon dioxide dielectric thickness due to quantum effects. Therefore, this invention uses hafnium oxide or yttrium oxide as the gate dielectric material. Hafnium dioxide, for instance, is an oxide with a high dielectric constant, a large bandgap, and good stability. Using hafnium dioxide effectively addresses the size limitations of traditional silicon dioxide structures.

[0058] Metal is deposited as the gate electrode on a portion of the gate dielectric near the source electrode and on the entire source electrode. In some embodiments, indium tin oxide (ITO) is used as the gate electrode material. ITO is a transparent conductive oxide with good conductivity and optical properties. As a transparent electrode, it has better light transmittance than ordinary metal materials. ITO can also switch between semiconductor and metallic properties by adjusting the O2 power and thickness during growth, reducing the amount of material required in device fabrication, simplifying the process, and greatly reducing the possibility of cross-contamination.

[0059] The gate and source electrodes of a transistor are shorted, forming a diode-like structure with rectification characteristics. Based on the aforementioned Schottky or Ohmic contacts between the source and drain electrodes and the thin film layer, a Schottky barrier is formed. After forming the diode-like structure, the short connection between the gate and source electrodes jointly regulates and fixes the Schottky barrier between the source electrode and the thin film layer, maintaining a high Schottky barrier to effectively suppress carrier migration and thus dark current. Simultaneously, the rectification characteristics of a diode are achieved on the basis of a transistor.

[0060] Under specific requirements and / or application scenarios, the height and width of the Schottky barrier between the source electrode and the thin film layer can be adjusted to some extent by adjusting the thickness of the gate electrode material and the gate dielectric.

[0061] For example, the source and drain electrodes are made of palladium (Pd) material, and the source and drain electrodes respectively achieve ohmic contact with the thin film layer, such as... Figure 2 The diagram shows the energy band structure of the corresponding thin-film detector under different bias voltages, illustrating the working principle of the thin-film detector under different bias voltages. Different bias voltages correspond to different positions of the diode output curve.

[0062] Specifically, Region I represents the conductive channel energy band at the contact area between the drain electrode and the thin film layer, Region II represents the conductive channel energy band controlled by the gate electrode, and Region III represents the conductive channel energy band jointly controlled by the source electrode and the gate electrode. Figure 2 (A) is a schematic diagram of the energy band structure of the thin-film detector in the off state (turn-on voltage is 0); Figure 2 (B) is a schematic diagram of the energy band when the turn-on voltage of the thin-film detector is exactly equal to the threshold voltage. Figure 2 (C) is a schematic diagram of the energy band structure of the thin-film detector in the on-state (on-state voltage is greater than threshold voltage). By comparing the three diagrams, it can be clearly observed that, regardless of the state of the thin-film detector of the present invention, there is a fixed and relatively high Schottky barrier in the conductive channel energy band jointly controlled by the source electrode and the gate electrode, i.e., between the source electrode and the thin film layer, which effectively suppresses carrier migration and achieves the function of suppressing dark current.

[0063] Furthermore, based on specific needs and / or specific application scenarios, the materials, width, thickness, and other dimensions of the source electrode, drain electrode, conductive channel, gate dielectric, and gate electrode of the thin-film detector provided by this invention can be adjusted accordingly. The specific implementation method will be described in detail in the following section on the fabrication method of the thin-film detector.

[0064] Specifically, with the gate and source electrodes of the transistor shorted, forming a diode-like structure, adjusting the thickness of the gate dielectric can adjust the width of the conductive channel band jointly controlled by the source and gate electrodes, i.e., adjusting the width of the Schottky barrier between the source electrode and the thin film layer; adjusting the material of the gate electrode (i.e., adjusting the work function of the gate electrode) can adjust the Fermi level of the conductive channel band controlled by the gate electrode, thereby adjusting the height difference of the conductive channel band jointly controlled by the source and gate electrodes, i.e., adjusting the height of the Schottky barrier between the source electrode and the thin film layer; adjusting the width of the conductive channel covered by the gate electrode can adjust the width of the conductive channel band controlled by the gate electrode, adjusting the corresponding current characteristics to meet specific needs and / or specific application scenarios, thus realizing the transistor configured as a diode.

[0065] Accordingly, the transistor-to-diode configuration refers to the operation in this invention where, based on the short-circuiting of the gate electrode and source electrode of the transistor to form a diode-like structure, the dimensions of each component within the thin-film detector are adjusted, thereby adjusting the corresponding characteristics to meet specific requirements and / or specific application scenarios.

[0066] Furthermore, the thin-film detector provided by this invention does not impose specific limitations on the source and drain electrodes, and Schottky contacts or ohmic contacts can be constructed according to the intended use of the device. For example, when the device is performing detection, the presence of dark current will generate noise, which will seriously interfere with the signal current. At this time, by forming a corresponding Schottky barrier through an ohmic contact, the dark current can be effectively suppressed, making the detection results more accurate.

[0067] This invention also provides a method for fabricating a thin-film detector based on a transistor-to-diode mode, such as... Figure 3 As shown, the method includes the following steps S101~S106:

[0068] Step S101: Obtain the first substrate layer.

[0069] Step S102: Grow a second substrate layer on the first substrate layer.

[0070] Step S103: Deposit a preset semiconductor material onto the second substrate layer using a preset deposition method to obtain a thin film layer.

[0071] Step S104: Preset regions for the source electrode and drain electrode are exposed on the thin film layer using electron beam lithography. A first preset metal material is deposited on the preset regions for the source electrode and drain electrode using electron beam evaporation to obtain the source electrode and drain electrode. A conductive channel is formed in the portion of the thin film layer between the source electrode and drain electrode.

[0072] Step S105: A predetermined region of the dielectric layer is exposed on the source electrode, drain electrode and conductive channel using electron beam lithography. A predetermined insulating material is deposited on the predetermined region of the dielectric layer using atomic layer deposition to obtain the dielectric layer. The dielectric layer is then used as the gate dielectric of the transistor.

[0073] Step S106: Expose the preset area of ​​the gate electrode on the dielectric layer and the source electrode using an electron beam lithography method, and deposit a second preset metal material on the preset area of ​​the gate electrode using an electron beam evaporation method to obtain the gate electrode; the gate electrode and the source electrode are connected.

[0074] In steps S101 and S102, the substrate material of the first substrate layer can be silicon, and the substrate material of the second substrate layer can be silicon dioxide. The second substrate layer is formed by thermal oxidation of the silicon substrate of the first substrate layer to produce silicon dioxide.

[0075] In step S103, a preset semiconductor material is deposited on the second substrate layer using a preset deposition method to obtain a thin film layer. The preset semiconductor material can be a two-dimensional material or a semiconductor thin film material, specifically, carbon nanotubes can be selected. The preset deposition method can be electrophoretic deposition, dry transfer, or wet transfer.

[0076] For example, carbon nanotubes are selected as the semiconductor material, and electrophoretic deposition is selected as the deposition method. Electrophoretic deposition is a simple, low-energy, and low-cost thin film preparation process. Carbon nanotube thin films based on electrophoresis technology have advantages such as low requirements on substrate type and shape, and room-temperature operation, making them particularly suitable for applications on complex and irregular substrates and low-melting-point materials. Specifically, the preparation method of carbon nanotube thin films can be divided into two parts: an electrophoresis process and a deposition process. In the electrophoresis process, under the action of a constant electric field, carbon nanotubes adsorbed with charged particles move directionally toward a certain electrode in a specific electrophoresis solution. In the deposition process, carbon nanotubes accumulate continuously on the electrode surface, eventually depositing into a dense and uniform thin film material.

[0077] In step S104, a first preset metal material is deposited on the preset areas of the source electrode and the drain electrode using an electron beam evaporation method. Electron beam evaporation is a type of physical vapor deposition. Unlike traditional evaporation methods, electron beam evaporation utilizes the coordination of an electromagnetic field to precisely bombard the target material in the crucible with high-energy electrons, causing it to melt and then deposit it on the substrate.

[0078] In some embodiments, the materials of the source electrode and the drain electrode, i.e. the first preset metal material, are palladium materials, or other metal materials such as titanium or gold materials.

[0079] In some embodiments, other suitable deposition methods may be selected based on the metal materials of the source and drain electrodes.

[0080] In this step, the source and drain electrodes achieve Schottky or ohmic contacts with the thin film layer.

[0081] In step S105, a preset insulating material is deposited on a preset area of ​​the dielectric layer using atomic layer deposition (ALD). ALD is a method that deposits material layer by layer onto a substrate surface in the form of single-atom films. During ALD, the chemical reaction of the new atomic film is directly related to the previous layer, ensuring that only one atomic layer is deposited per reaction. This method meets the demands of continuously reducing device and material dimensions in technologies such as microelectronics and deep submicron chips, reducing the thickness of material films to the order of several nanometers.

[0082] In some embodiments, when atomic layer deposition is not used, a metal with a thickness of nanometers can be deposited on a predetermined area of ​​the dielectric layer and then subjected to high-temperature oxidation, which can also obtain a dielectric layer that meets the thickness requirements.

[0083] In some embodiments, the preset insulating material is selected from metal oxide materials such as hafnium oxide or yttrium oxide.

[0084] In step S106, a second preset metal material is deposited on a preset area of ​​the gate electrode using an electron beam evaporation method, which is consistent with the method described in step S104.

[0085] In some embodiments, other suitable deposition methods may be selected based on the material of the gate electrode.

[0086] In some embodiments, the second preset metal material is indium tin oxide.

[0087] Finally, the gate electrode covers part of the gate dielectric and all of the source electrode, shorting the gate and source electrodes to form a diode-like structure. Based on the Schottky contact between the source and drain electrodes and the thin film layer described above, a Schottky barrier is formed. After the diode-like structure is formed, the shorting between the gate and source electrodes jointly regulates and fixes the Schottky barrier between the source electrode and the thin film layer, maintaining a high Schottky barrier between the source electrode and the thin film layer to effectively suppress carrier migration and thus suppress dark current.

[0088] Corresponding to the transistor-to-diode configuration described above, when the gate and source electrodes of the transistor are shorted, forming a diode-like structure, and the dimensions of the components within the thin-film detector need to be adjusted, the dimensions of the corresponding components only need to be modified during electron beam exposure in steps S105 and / or S106. For example, in step S105, by adjusting the thickness of the gate dielectric, the width of the conductive channel band controlled by both the source and gate electrodes can be adjusted, i.e., the width of the Schottky barrier between the source electrode and the thin film layer can be adjusted. In step S106, by adjusting the width of the conductive channel covered by the gate electrode, the width of the conductive channel band controlled by the gate electrode can be adjusted. Simultaneously, the Fermi level of the conductive channel band controlled by the gate electrode can be adjusted by adjusting the material of the gate electrode (i.e., adjusting the work function of the gate electrode), thereby adjusting the height difference of the conductive channel band controlled by both the source and gate electrodes, i.e., adjusting the height of the Schottky barrier between the source electrode and the thin film layer. This achieves the transistor-to-diode configuration to meet specific needs and / or application scenarios.

[0089] In summary, this invention provides a thin-film detector based on a transistor-to-diode configuration and its fabrication method, comprising: growing a source electrode and a drain electrode on a semiconductor thin film layer, wherein the source electrode and the drain electrode respectively form a Schottky contact or an ohmic contact with the thin film layer; growing a gate electrode on the source electrode and a gate dielectric, wherein the source electrode and the gate electrode are short-circuited to form a diode-like structure; and through the joint control of the gate electrode and the source electrode, a Schottky barrier of fixed height is formed between the source electrode and the thin film layer, effectively suppressing carrier migration and thus suppressing dark current; at the same time, it has rectification characteristics similar to a diode, greatly improving photoelectric detection performance and stability.

[0090] Furthermore, the thin film layer has the characteristic of being easily tunable. In the fabrication method of thin film detector based on transistor-to-diode mode, the width of the Schottky barrier between the source electrode and the thin film layer can be effectively controlled by adjusting the thickness of the gate dielectric; the height of the Schottky barrier between the source electrode and the thin film layer can be effectively controlled by adjusting the material of the gate electrode, thereby meeting specific needs and / or specific application scenarios, and having universal applicability.

[0091] It should be clarified that the present invention is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present invention is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of the present invention.

[0092] In this invention, features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, and / or combined with or in place of features of other embodiments.

[0093] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, various modifications and variations of the embodiments of the present invention are possible. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thin-film detector based on a transistor configured as a diode, characterized in that, include: First substrate layer; A second substrate layer is disposed above the first substrate layer, and the second substrate layer is made of an insulating material; A thin film layer is disposed above the second substrate layer; the thin film material of the thin film layer is selected as carbon nanotubes. A source electrode and a drain electrode are disposed above the thin film layer, and the source electrode and the drain electrode respectively form a Schottky contact with the thin film layer; a conductive channel is formed in the thin film layer between the source electrode and the drain electrode; A dielectric layer is disposed above the source electrode, the conductive channel, and the drain electrode; A gate electrode is disposed above the dielectric layer and the source electrode, and the gate electrode and the source electrode are short-circuited.

2. The thin-film detector based on a transistor configured as a diode according to claim 1, characterized in that, The substrate material of the first substrate layer is silicon; the substrate material of the second substrate layer is silicon dioxide.

3. The thin-film detector based on a transistor configured as a diode according to claim 1, characterized in that, The gate electrode is made of indium tin oxide.

4. A method for fabricating a thin-film detector based on a transistor connected in diode mode, characterized in that, This method is used to fabricate a thin-film detector based on a transistor-to-diode configuration as described in any one of claims 1 to 3, the method comprising the following steps: Obtain the first substrate layer; A second substrate layer is grown on the first substrate layer; A thin film layer is obtained by depositing a predetermined semiconductor material onto the second substrate layer using a predetermined deposition method; the predetermined semiconductor material is selected as carbon nanotubes. Preset regions for the source electrode and the drain electrode are exposed on the thin film layer using electron beam lithography. A first preset metal material is deposited on the preset regions for the source electrode and the drain electrode using electron beam evaporation to obtain the source electrode and the drain electrode. The source electrode and the drain electrode respectively achieve Schottky contact with the thin film layer. A conductive channel is formed in the portion of the thin film layer between the source electrode and the drain electrode. A predetermined region of the dielectric layer is exposed on the source electrode, the drain electrode, and the conductive channel using an electron beam lithography method. A predetermined insulating material is deposited on the predetermined region of the dielectric layer using an atomic layer deposition method, or a metal with a nanometer-thickness is deposited on the predetermined region of the dielectric layer and then subjected to high-temperature oxidation to obtain the dielectric layer. The dielectric layer is used as the gate dielectric of the transistor. The predetermined insulating material is selected from hafnium oxide or yttrium oxide. A predetermined region of the gate electrode is exposed on the dielectric layer and the source electrode using an electron beam lithography method. A second predetermined metal material is deposited on the predetermined region of the gate electrode using an electron beam evaporation method to obtain the gate electrode. The gate electrode and the source electrode are short-circuited.

5. The fabrication method of the thin-film detector based on a transistor-to-diode mode according to claim 4, characterized in that, The preset deposition method is an electrophoretic deposition method, a dry transfer method, or a wet transfer method.

6. The method for fabricating a thin-film detector based on a transistor-to-diode mode according to claim 4, characterized in that, The first preset metal material includes at least one or more combinations of palladium, titanium and gold; the second preset metal material is indium tin oxide.

7. The fabrication method of the thin-film detector based on a transistor-to-diode mode according to claim 4, characterized in that, The predetermined area of ​​the dielectric layer partially covers the source electrode, and the gate electrode is directly grown on the surface of the portion of the source electrode not covered and part of the conductive channel region.

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