Carbon-based visible-infrared photodetector using carbon nanohorns and method for manufacturing the same

Abstract

The application discloses a carbon-based visible-infrared photodetector adopting carbon nanohorns and a preparation method thereof, which comprises a substrate, a composite carbon-based film located on the substrate, a source electrode and a drain electrode; the composite carbon-based film comprises a carbon nanotube network or array film and carbon nanohorns deposited in sequence; the drain electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate, and the source electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate. Advantages of the application are as follows: 1) the carbon nanohorns have good conductivity, which is beneficial to the transport of photo-generated carriers; 2) the carbon nanohorn structure has good absorption to infrared light; and 3) the device is simple to manufacture and compatible with traditional semiconductor processes.

Description

Technical Field

[0001] The present invention belongs to the technical field of infrared photoelectric detectors, and in particular relates to a carbon-based visible-infrared photoelectric detector using carbon nanohorns and a preparation method thereof. Background Art

[0002] Current research progress, both domestically and internationally, indicates that carbon-based infrared photodetectors, primarily based on carbon nanotubes (CNTs), have achieved remarkable success. Semiconducting CNTs possess a direct band gap, and their delocalized π-electron system enables light absorption properties with a wide energy range. Under illumination from infrared to visible light, they generate photogenerated carriers with high carrier mobility. Dense CNT networks or arrays also exhibit strong light absorption properties. However, due to their one-dimensional structure, CNTs exhibit strong electron-hole interactions, forming excitons rather than free electrons and holes, which hinders the efficient separation and transport of photogenerated carriers to the electrodes. To further effectively separate photogenerated carriers within CNTs, constructing a type II heterogeneous band structure at the CNT interface is an effective approach. Carbon nanohorns, a unique device design consisting of a single layer, facilitates increased phototransistor gain and allows for gate voltage control of the device's photocurrent.

[0003] Although some progress has been made in the research of carbon-based infrared photodetectors, there are still problems in this field. The main problem is that it is difficult to ensure high responsiveness and fast photoelectric response at the same time. Summary of the Invention

[0004] Technical problems solved: In response to the above technical problems, the present invention provides a carbon-based visible-infrared photodetector using carbon nanohorns and a preparation method thereof, which can effectively solve the problems of insufficient responsiveness and response rate of the detector.

[0005] Technical solution: In the first aspect, the present invention provides a carbon-based visible-infrared photodetector using carbon nanohorns, comprising a substrate, a composite carbon-based film located on the substrate, a source electrode, and a drain electrode; the composite carbon-based film comprises a carbon nanotube network or array and carbon nanohorns deposited successively; the drain electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate, and the source electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate.

[0006] Preferably, the substrate is a combination of one or more of a hard substrate Si, GaN, SiC, Al2O3, GaAs, SiO2, AlN, HfO2, Y2O3 or a flexible substrate PEN, PI, PET, HMDS, BCB.

[0007] Preferably, the composite carbon-based film comprises carbon nanotube arrays and carbon nanohorns stacked in an alternating manner, and the mass ratio of the carbon nanotube arrays to the carbon nanohorns is 1-100,000:1-100,000.

[0008] Preferably, the thickness of the source electrode and the drain electrode are both 1 nm to 10000 nm.

[0009] Preferably, the material of the source electrode and the drain electrode is a combination of one or more of Au, Pd, Al, Cu, Ni, Ti, Ag, Cr, Mo, W, and Fe.

[0010] Furthermore, when the source electrode and the drain electrode are made of a combination of two metals, the mass ratio of the two metals is 1-1000:1-1000.

[0011] In a second aspect, the present invention provides a carbon-based visible-infrared photodetector using carbon nanohorns. Compared with the detector provided in the first aspect, the detector further includes a gate electrode, which is arranged above or below the carbon nanotubes.

[0012] In a third aspect, the present invention provides a method for preparing the detector according to the first aspect, comprising the following steps:

[0013] S1. Prepare substrate;

[0014] S2. depositing a composite carbon-based film on a substrate;

[0015] S3. Defining a device source electrode region and depositing a source electrode on the composite carbon-based film, defining a device drain electrode region and depositing a drain electrode;

[0016] S4. Define the active area of ​​the device, use photoresist, electron beam glue, polymer or metal as a mask to protect the active area, and remove the surrounding exposed non-active area composite carbon-based film by etching.

[0017] Preferably, the method for depositing the composite carbon-based film in step S2 is a combination of one or more of chemical vapor deposition on-wafer growth, deposition by immersion in a dispersion, spin coating the dispersion, spraying the dispersion, wet transfer, dry transfer, inkjet printing, screen printing or nanotransfer printing.

[0018] In a fourth aspect, the present invention provides a method for preparing the detector according to the first aspect, comprising the following steps:

[0019] S1. Prepare substrate;

[0020] S2. defining a device source electrode region on the substrate and depositing a source electrode, and then depositing a composite carbon-based film so that the composite carbon-based film covers the source electrode;

[0021] S3. depositing a drain electrode on the composite carbon-based film;

[0022] S4. Define the active area of ​​the device, use photoresist as a mask to protect the active area, and remove the surrounding exposed non-active area composite carbon-based film by etching.

[0023] Beneficial effects of the present invention:

[0024] 1) The present invention utilizes the excellent electrical conductivity and light absorption properties of carbon nanohorns to form a heterojunction at the interface with carbon-based semiconductor films such as carbon nanotubes. This generates a built-in electric field that promotes the separation of photogenerated electron-hole pairs and also provides a channel for carrier transmission, thereby improving the detector's responsivity and response rate.

[0025] 2) The device is easy to manufacture and compatible with traditional semiconductor processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of the preparation process of the carbon nanotube array-carbon nanohorn planar heterojunction visible-infrared photodetector on a silicon dioxide substrate in Example 1 of the present invention, wherein (a) is a schematic diagram of the substrate, (b) is a schematic diagram of depositing a composite carbon-based film on the substrate, (c) is a schematic diagram of depositing a source electrode on the composite carbon-based film, (d) is a schematic diagram of depositing a drain electrode on the composite carbon-based film, (e) is a schematic diagram of applying a photoresist mask, and (f) is a schematic diagram after etching and removing the mask;

[0027] Figure 2 Schematic diagram of the manufacturing process steps of a vertically structured visible-infrared photodetector comprising a carbon nanotube array, carbon nanohorn, and graphene sandwich on a silicon dioxide substrate in Example 2 of the present invention, wherein (a) is a schematic diagram of the substrate, (b) is a schematic diagram of depositing a source electrode on the substrate, (c) is a schematic diagram of depositing a carbon nanotube array and carbon nanohorns in a composite carbon-based film, (d) is a schematic diagram of depositing graphene in the composite carbon-based film, (e) is a schematic diagram of depositing a drain electrode, (f) is a schematic diagram of applying a photoresist mask, and (g) is a schematic diagram after etching and mask removal;

[0028] Explanation of the accompanying symbols: 1. substrate; 2. composite carbon-based film; 3. source electrode; 4. drain electrode; 5. photoresist mask. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the following embodiments:

[0030] Example 1

[0031] A carbon-based infrared photodetector using carbon nanohorns comprises a Si substrate 1, a composite carbon-based film 2 located on substrate 1, a source electrode 3, and a drain electrode 4. The substrate is a hard substrate selected from Si, GaN, SiC, Al2O3, GaAs, SiO2, AlN, HfO2, Y2O3, or a flexible substrate selected from PEN, PI, PET, HMDS, and BCB, or a combination thereof, either epitaxially or by bonding. The composite carbon-based film 2 comprises a carbon nanotube array and carbon nanohorns, with no restrictions on the number or order of layers. The porous complex structure of the carbon nanohorns has a high specific surface area and strong absorption of near-infrared light, which helps improve the detector's responsivity. Like other low-dimensional carbon materials, carbon nanohorns possess excellent electrical conductivity, facilitating the rapid transport of photogenerated carriers. Furthermore, carbon nanohorns easily associate or disperse in organic solutions, facilitating functionalization. By spin-coating a carbon nanohorn dispersion so that it is evenly distributed on the surface of the carbon nanotube array to form a heterojunction, the carbon nanohorns with a large specific surface area structure can capture photons more effectively. The photons absorbed in the carbon nanohorns generate strongly bound excitons, which diffuse to the carbon nanotube / carbon nanohorn interface and are dissociated by the built-in electric field of the interface. Electrons are transmitted more quickly through the carbon nanohorns, and holes are transferred to the carbon nanotubes for conduction, thereby significantly enhancing the responsiveness and response rate of the detector.

[0032] The drain electrode 4 is located on the composite carbon-based film 2 , and the source electrode 3 is located on the composite carbon-based film 2 . The thickness of the source electrode 3 and the drain electrode 4 are both 1 nm to 1000 nm.

[0033] The source electrode 3 and the drain electrode 4 can be one or a combination of two of Au, Pd, Al, Cu, Ni, Ti, Ag, Cr, Mo, W, and Fe. When the source electrode 3 and the drain electrode 4 are a combination of two metals, the mass ratio of the two metals is 1 to 1000:1 to 1000. In this embodiment, the source electrode 3 is Ti and Au in a mass ratio of 1 to 1000:1 to 1000, and the drain electrode 4 is Pd and Au in a mass ratio of 1 to 1000:1 to 1000.

[0034] The preparation method of the carbon-based visible-infrared photodetector using carbon nanohorns is as follows: Figure 1 As shown, the following steps are included:

[0035] S1. Figure 1 As shown in (a), a substrate 1 is prepared;

[0036] S2. Figure 1As shown in (b), a composite carbon-based film is deposited on a substrate 1 by one or more of chemical vapor deposition on-wafer growth, deposition by immersion in a dispersion, spin coating the dispersion, spraying the dispersion, wet transfer, dry transfer, inkjet printing, screen printing, or nanotransfer printing. In this embodiment, a layer of carbon nanotube array is first deposited on the substrate 1, and then a carbon nanohorn dispersion is spin-coated on the carbon nanotube array to obtain a composite carbon-based film 2;

[0037] S3. Figure 1 As shown in (c) and (d), the device source electrode region is defined on the composite carbon-based film 2 by ultraviolet exposure, deep ultraviolet exposure, electron beam writing or nano-transfer printing technology, and the source electrode 3 is deposited by electron beam evaporation and lift-off process. The device drain electrode region is defined and the drain electrode 4 is deposited by electron beam evaporation and lift-off process.

[0038] S4. As shown in Figures (e) and (f), the active area of ​​the device is first defined by ultraviolet exposure, deep ultraviolet exposure, electron beam writing or nano-transfer technology, the active area is protected by a photoresist mask 5, and the surrounding exposed non-active area composite carbon-based film 2 is removed by etching, wherein the etching method of the non-active area composite carbon-based film 2 includes inductively coupled plasma etching, reactive ion etching or oxygen plasma gluing. In this embodiment, the exposed material around is removed by gluing with an oxygen plasma gluing machine, and finally acetone alcohol is used for de-gluing.

[0039] Example 2

[0040] A carbon-based visible-infrared photodetector using carbon nanohorns comprises a SiO2 substrate 1, a composite carbon-based film 2 located on substrate 1, a source electrode 3, and a drain electrode 4. The composite carbon-based film 2 comprises a carbon nanotube array, carbon nanohorns, and graphene. The porous complex structure of the carbon nanohorns has a high specific surface area and strong absorption of near-infrared light, which helps improve the detector's responsivity. Like other low-dimensional carbon materials, carbon nanohorns have excellent electrical conductivity, facilitating the rapid transport of photogenerated carriers. Furthermore, carbon nanohorns easily associate or disperse in organic solutions, facilitating functionalization. By spin-coating a carbon nanohorn dispersion so that it is evenly distributed on the surface of the carbon nanotube array to form a heterojunction, the carbon nanohorns with a large specific surface area structure can capture photons more effectively. The photons absorbed in the carbon nanohorns generate strongly bound excitons, which diffuse to the carbon nanotube / carbon nanohorn interface and are dissociated by the built-in electric field of the interface. Electrons are transmitted more quickly through the carbon nanohorns, and holes are transferred to the carbon nanotubes for conduction, thereby significantly enhancing the responsiveness and response rate of the detector.

[0041] The drain electrode 4 is located on the composite carbon-based film 2 , and the source electrode 3 is located between the composite carbon-based film 2 and the substrate 1 . The thickness of the source electrode 3 and the drain electrode 4 are both 1 nm to 1000 nm.

[0042] The source electrode 3 and the drain electrode 4 can be one or a combination of two of Au, Pd, Al, Cu, Ni, Ti, Ag, Cr, Mo, W, and Fe. When the source electrode 3 and the drain electrode 4 are a combination of two metals, the mass ratio of the two metals is 1 to 1000:1 to 1000. In this embodiment, the source electrode 3 is Ti and Au in a mass ratio of 1 to 1000:1 to 1000, and the drain electrode 4 is Pd and Au in a mass ratio of 1 to 1000:1 to 1000.

[0043] The preparation method of the carbon-based infrared photodetector using carbon nanohorns is as follows: Figure 2 As shown, the following steps are included:

[0044] S1. Figure 2 As shown in (a), a substrate 1 is prepared;

[0045] S2. Figure 2 As shown in (b), the device source electrode region is defined by ultraviolet exposure, deep ultraviolet exposure, electron beam writing or nano-transfer printing technology, and the source electrode 3 is deposited by electron beam evaporation and lift-off process;

[0046] Afterwards Figure 2 As shown in (c), a composite carbon-based film 2 is deposited on a substrate 1 by chemical vapor deposition, deposition by immersion in a dispersion, spin coating the dispersion, spraying the dispersion, wet transfer, dry transfer, inkjet printing, screen printing, or nano-transfer printing, and the composite carbon-based film 2 covers the source electrode 3. In this embodiment, the composite carbon-based film 2 includes a carbon nanotube array, carbon nanohorns, and graphene. The carbon nanotube array dispersion is first spin-coated, and then the carbon nanohorn dispersion is spin-coated. Figure 2 (d) shows that the CVD single-layer graphene on the copper substrate is transferred to the upper layer by wet transfer method;

[0047] S3. Figure 2 As shown in (e), the device drain electrode region is defined on the composite carbon-based film 2 by ultraviolet exposure, deep ultraviolet exposure, electron beam writing or nano-transfer printing technology, and the drain electrode 4 is deposited;

[0048] S4. Figure 2 As shown in (f) and (g), the active area of ​​the device is first defined by ultraviolet exposure, deep ultraviolet exposure, electron beam writing or nano-transfer technology, the active area is protected by a photoresist mask 5, and the surrounding exposed non-active area composite carbon-based film 2 is removed by etching, wherein the etching method of the non-active area composite carbon-based film 2 includes inductively coupled plasma etching, reactive ion etching or oxygen plasma gluing. In this embodiment, the exposed material around is removed by gluing with an oxygen plasma gluing machine, and finally acetone alcohol is used for de-gluing.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A carbon-based visible-infrared photodetector using carbon nanohorns, characterized by: It includes a substrate, a composite carbon-based film located on the substrate, a source electrode and a drain electrode; the composite carbon-based film includes a carbon nanotube network or array and carbon nanohorns deposited in sequence; the drain electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate, and the source electrode is located on the composite carbon-based film or between the composite carbon-based film and the substrate; the composite carbon-based film includes carbon nanotube arrays and carbon nanohorns stacked in an alternating manner, and the mass ratio of the carbon nanotube arrays to the carbon nanohorns is 1 to 100,000:1 to 100,000; and it also includes a gate electrode, which is arranged above or below the carbon nanotubes.

2. The carbon-based visible-infrared photodetector using carbon nanohorns according to claim 1, characterized in that: The substrate is a combination of one or more of a hard substrate Si, GaN, SiC, Al2O3, GaAs, SiO2, AlN, HfO2, Y2O3 or a flexible substrate PEN, PI, PET, HMDS, BCB.

3. The carbon-based visible-infrared photodetector using carbon nanohorns according to claim 1, characterized in that: The thickness of the source electrode and the drain electrode are both 1 nm to 10000 nm.

4. The carbon-based visible-infrared photodetector using carbon nanohorns according to claim 1, characterized in that: The material of the source electrode and the drain electrode is a combination of one or more of Au, Pd, Al, Cu, Ni, Ti, Ag, Cr, Mo, W, and Fe.

5. The carbon-based visible-infrared photodetector using carbon nanohorns according to claim 4, characterized in that: When the source electrode and the drain electrode are made of a combination of two metals, the mass ratio of the two metals is 1-1000:1-1000.

6. A method for preparing the detector according to claim 1, characterized in that: The following steps are involved: S1. Prepare substrate; S2. depositing a composite carbon-based film on a substrate; S3. Defining a device source electrode region and depositing a source electrode on the composite carbon-based film, defining a device drain electrode region and depositing a drain electrode; S4. Define the active area of ​​the device, use photoresist, electron beam glue, polymer or metal as a mask to protect the active area, and remove the surrounding exposed non-active area composite carbon-based film by etching.

7. The method for preparing a carbon-based visible-infrared photodetector using carbon nanohorns according to claim 6, wherein: The method for depositing the composite carbon-based film in step S2 is a combination of one or more of chemical vapor deposition on-wafer growth, deposition by immersion in a dispersion, spin coating the dispersion, spraying the dispersion, wet transfer, dry transfer, inkjet printing, screen printing or nano transfer printing.

8. A method for preparing the detector according to claim 1, characterized in that: The following steps are involved: S1. Prepare substrate; S2. defining a device source electrode region on the substrate and depositing a source electrode, and then depositing a composite carbon-based film so that the composite carbon-based film covers the source electrode; S3. depositing a drain electrode on the composite carbon-based film; S4. Define the active area of ​​the device, use photoresist as a mask to protect the active area, and remove the surrounding exposed non-active area composite carbon-based film by etching.

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