阅读说明：本技术 一种SiC基氧化镓微米线的光电探测器及其制备方法 (Photoelectric detector of SiC-based gallium oxide micron line and preparation method thereof ) 是由 李京波 张帅 赵艳 汪争 张龙 周贝尔 于 2021-06-09 设计创作，主要内容包括：本发明涉及一种SiC基氧化镓微米线的光电探测器及其制备方法,方法包括：制备氧化镓微米线；将所述氧化镓微米线转移至第一衬底上,其中,所述第一衬底包括n～(+)SiC衬底层和位于所述n～(+)SiC衬底层上的n～(-)SiC衬底层；在惰性气体中对所述氧化镓微米线和所述第一衬底进行退火处理；在所述氧化镓微米线两端制备源电极和漏电极。本发明在SiC上制备了氧化镓微米线,使得所制备的光电探测器使用具有外延轻掺杂SiC衬底层做为感光衬底,制作了一维的氧化镓微米线与三维的SiC异质结构,具有较好的紫外光探测能力。(The invention relates to a photoelectric detector of SiC-based gallium oxide microwire and a preparation method thereof, wherein the method comprises the following steps: preparing gallium oxide microwires; transferring the gallium oxide microwires onto a first substrate, wherein the first substrate comprises n + SiC substrate layer and the layer located at n + N on SiC substrate layer ‑ A SiC substrate layer; annealing the gallium oxide microwires and the first substrate in an inert gas; on the gallium oxide micron lineAnd preparing a source electrode and a drain electrode. According to the invention, the gallium oxide microwire is prepared on SiC, so that the prepared photoelectric detector uses the epitaxial lightly doped SiC substrate layer as a photosensitive substrate, and a one-dimensional gallium oxide microwire and a three-dimensional SiC heterostructure are prepared, thereby having better ultraviolet light detection capability.)

1. A preparation method of a photoelectric detector of SiC-based gallium oxide microwire is characterized by comprising the following steps:

preparing gallium oxide microwires;

transferring the gallium oxide microwires onto a first substrate, wherein the first substrate comprises n⁺SiC substrate layer and the layer located at n⁺N on SiC substrate layer^-A SiC substrate layer;

annealing the gallium oxide microwires and the first substrate in an inert gas;

and preparing a source electrode and a drain electrode at two ends of the gallium oxide microwire.

2. The method of manufacturing a photodetector according to claim 1, wherein the manufacturing of the gallium oxide microwire comprises:

cleaning a second substrate, wherein the second substrate comprises a Si substrate layer and SiO positioned on the Si substrate layer₂A substrate layer;

preparing the gallium oxide microwire on the second substrate by adopting a chemical vapor deposition method;

and putting the second substrate on which the gallium oxide microwires grow into an absolute ethyl alcohol solution, and then carrying out ultrasonic treatment to enable the gallium oxide microwires to completely fall off from the second substrate into the absolute ethyl alcohol solution.

3. The method of claim 2, wherein cleaning the second substrate comprises:

and respectively carrying out ultrasonic treatment on the second substrate by using acetone and isopropanol, and then cleaning the second substrate by using ozone ultraviolet or oxygen plasma.

4. The method of claim 2, wherein transferring the gallium oxide microwire onto a first substrate comprises:

and sucking the absolute ethyl alcohol solution mixed with the gallium oxide microwires onto the first substrate.

5. The method of claim 1, wherein annealing the gallium oxide microwire and the first substrate in an inert gas comprises:

and annealing the gallium oxide microwire and the first substrate under the conditions that the inert gas is nitrogen, the annealing temperature is 100-200 ℃ and the annealing time is 10-60 min.

6. The method of claim 1, wherein the step of forming a source electrode and a drain electrode at both ends of the gallium oxide microwire comprises:

spin-coating a photoresist on the first substrate, and then heating and drying;

forming an electrode pattern by exposure and development;

and preparing a source electrode and a drain electrode at two ends of the gallium oxide microwire by adopting an electron beam evaporation coating method.

7. The method of manufacturing a photodetector according to claim 6, wherein the forming of the electrode pattern by exposure and development comprises:

and forming the electrode pattern by exposure and development, wherein the developing solution is formed by mixing tetramethylammonium hydroxide solution and deionized water, and the development time is 20-60 s.

8. The method of claim 1, wherein n is the same as n⁺The thickness of the SiC substrate layer is 180-375 mu m, and n is^-The thickness of the SiC substrate layer is 0.5-11 mu m.

9. The method for manufacturing a photodetector according to claim 1, further comprising, after the source electrode and the drain electrode are manufactured at both ends of the gallium oxide microwire:

and preparing a gate electrode on one side of the first substrate far away from the gallium oxide microwire.

10. A photodetector of SiC-based gallium oxide microwire, characterized by being prepared by the method of any one of claims 1 to 9, the photodetector comprising:

a first substrate comprising n⁺SiC substrate layer and the layer located at n⁺N on SiC substrate layer^-A SiC substrate layer;

gallium oxide microwires on the first substrate;

a source electrode and a drain electrode on the first substrate and at both ends of the gallium oxide microwire;

and the gate electrode is positioned on the lower surface of the first substrate.

Technical Field

The invention belongs to the technical field of semiconductor devices, and relates to a photoelectric detector of a SiC-based gallium oxide micron line and a preparation method thereof.

Background

The photoelectric detection technology is one of the indispensable technologies in human modern life, and particularly has strong absorption effect of the atmospheric ozone layer, so that the ultraviolet light in sunlight cannot reach the surface of the earth. Therefore, the gallium oxide micron line has higher requirements on the detection of a sunlight blind detector, the forbidden band width of the gallium oxide micron line is 4.9eV, the gallium oxide micron line and the ultraviolet spectrum frequency band correspond to a better sunlight blind ultraviolet detector candidate material, and silicon carbide (SiC) is also a third generation wide forbidden band semiconductor with excellent performance, and has the characteristics of larger forbidden band width (3.3eV), higher ultraviolet light absorption rate, high breakdown electric field width, high saturated electron drift rate, high thermal conductivity and the like.

However, most of the existing gallium oxide is thin film, which is not favorable for integration, and the existing gallium oxide detector has the disadvantages of slow response speed and poor heat dissipation, thus limiting the application of the existing gallium oxide detector in related fields.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a photoelectric detector of SiC-based gallium oxide microwire and a preparation method thereof. The technical problem to be solved by the invention is realized by the following technical scheme:

the embodiment of the invention provides a preparation method of a photoelectric detector of SiC-based gallium oxide microwire, which comprises the following steps:

preparing gallium oxide microwires;

transferring the gallium oxide microwires onto a first substrate, wherein the first substrate comprises n⁺SiC substrate layer and the layer located at n⁺N on SiC substrate layer^-A SiC substrate layer;

annealing the gallium oxide microwires and the first substrate in an inert gas;

and preparing a source electrode and a drain electrode at two ends of the gallium oxide microwire.

In one embodiment of the present invention, the gallium oxide microwire is prepared comprising:

cleaning a second substrate, wherein the second substrate comprises a Si substrate layer and SiO positioned on the Si substrate layer₂A substrate layer;

preparing the gallium oxide microwire on the second substrate by adopting a chemical vapor deposition method;

and putting the second substrate on which the gallium oxide microwires grow into an absolute ethyl alcohol solution, and then carrying out ultrasonic treatment to enable the gallium oxide microwires to completely fall off from the second substrate into the absolute ethyl alcohol solution.

In one embodiment of the present invention, cleaning the second substrate comprises:

and respectively carrying out ultrasonic treatment on the second substrate by using acetone and isopropanol, and then cleaning the second substrate by using ozone ultraviolet or oxygen plasma.

In one embodiment of the present invention, transferring the gallium oxide microwires onto a first substrate comprises:

and sucking the absolute ethyl alcohol solution mixed with the gallium oxide microwires onto the first substrate.

In one embodiment of the present invention, annealing the gallium oxide microwire and the first substrate in an inert gas comprises:

and annealing the gallium oxide microwire and the first substrate under the conditions that the inert gas is nitrogen, the annealing temperature is 100-200 ℃ and the annealing time is 10-60 min.

In one embodiment of the present invention, preparing a source electrode and a drain electrode at both ends of the gallium oxide microwire comprises:

spin-coating a photoresist on the first substrate, and then heating and drying;

forming an electrode pattern by exposure and development;

and preparing a source electrode and a drain electrode at two ends of the gallium oxide microwire by adopting an electron beam evaporation coating method.

In one embodiment of the present invention, forming an electrode pattern by exposure and development includes:

and forming the electrode pattern by exposure and development, wherein the developing solution is formed by mixing tetramethylammonium hydroxide solution and deionized water, and the development time is 20-60 s.

In one embodiment of the invention, said n⁺The thickness of the SiC substrate layer is 180-375 mu m, and n is^-The thickness of the SiC substrate layer is 0.5-11 mu m.

In an embodiment of the present invention, after preparing a source electrode and a drain electrode at both ends of the gallium oxide microwire, the method further comprises:

and preparing a gate electrode on one side of the first substrate far away from the gallium oxide microwire.

Another embodiment of the present invention provides a SiC-based gallium oxide microwire photodetector, which is prepared by the preparation method according to any one of the above embodiments, and includes:

a first substrate comprising n⁺SiC substrate layer and the layer located at n⁺N on SiC substrate layer^-A SiC substrate layer;

gallium oxide microwires on the first substrate;

a source electrode and a drain electrode on the first substrate and at both ends of the gallium oxide microwire;

and the gate electrode is positioned on the lower surface of the first substrate.

Compared with the prior art, the invention has the beneficial effects that:

according to the invention, the gallium oxide microwire is prepared on SiC, so that the prepared photoelectric detector uses the epitaxial lightly doped SiC substrate layer as a photosensitive substrate, and a one-dimensional gallium oxide microwire and a three-dimensional SiC heterostructure are prepared, thereby having better ultraviolet light detection capability.

The SiC substrate used by the invention has good heat dissipation capability and high pressure resistance capability, not only meets the high pressure driving requirement of gallium oxide, but also makes up the defect of insufficient heat dissipation of gallium oxide.

The preparation method of the photoelectric detector provided by the invention has the advantages of simple preparation process, mature testing technology and low manufacturing cost, and is very beneficial to the future commercial popularization.

Other aspects and features of the present invention will become apparent from the following detailed description, which proceeds with reference to the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.

Drawings

Fig. 1 is a schematic flow chart of a method for manufacturing a SiC-based gallium oxide microwire photodetector according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a SiC-based gallium oxide microwire photodetector according to an embodiment of the present invention;

FIG. 3 is a Scanning Electron Microscope (SEM) view of a SiC-based gallium oxide microwire photodetector provided by an embodiment of the present invention;

FIG. 4 shows that the optical power intensity of the photodetector of SiC-based gallium oxide microwire provided by the embodiment of the invention is 244.8 μ W-cm^-2Current-voltage curve under 254nm ultraviolet light.

FIG. 5 shows that when Vds of the photodetector of the SiC-based gallium oxide microwire provided by the embodiment of the invention is-2V, the optical power intensity is 244.8 μ W-cm^-2Photocurrent versus time for 254nm uv light.

FIG. 6 shows that when Vds of the photodetector of the SiC-based gallium oxide microwire provided by the embodiment of the invention is-2V, the optical power intensity is 244.8 μ W-cm^-2Ultraviolet light of 254nmRise-fall time diagram of (2).

Reference numerals:

gallium oxide microwire-1; a first substrate-2; a source electrode-3; a drain electrode-4; a gate electrode-5; n is⁺A SiC substrate layer-21; n is^-SiC substrate layer-22.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.

Example one

Fig. 1 is a schematic flow chart of a method for manufacturing a SiC-based gallium oxide microwire photodetector according to an embodiment of the present invention, and fig. 2 is a schematic structural diagram of a SiC-based gallium oxide microwire photodetector according to an embodiment of the present invention. The invention provides a preparation method of a photoelectric detector of SiC-based gallium oxide microwire, which comprises the following steps:

step 1, gallium oxide (Ga) preparation₂O₃) Micron line 1.

Step 1.1, cleaning a second substrate, wherein the second substrate comprises a Si substrate layer and SiO positioned on the Si substrate layer₂A substrate layer.

Specifically, the second substrate is subjected to ultrasonic treatment with acetone and isopropyl alcohol, respectively, and then cleaned with ozone ultraviolet or oxygen plasma.

In one specific embodiment, the second substrate is first sonicated with acetone, isopropanol, each for 20 min; and then cleaning in ozone ultraviolet or oxygen plasma for 5min, wherein the oxygen flow is 50sccm, and the plasma power is 100W.

Step 1.2, preparing the gallium oxide microwire 1 on the second substrate by adopting a chemical vapor deposition method.

Specifically, a gallium oxide microwire 1 is prepared on a second substrate by adopting a chemical vapor deposition method, wherein the growth temperature is 850-1000 ℃, the growth time is 5-10 minutes, the carrier gas is nitrogen or argon, and the gas flow is 50-100 sccm.

And step 1.3, putting the second substrate on which the gallium oxide microwire 1 grows into the absolute ethyl alcohol solution, and then carrying out ultrasonic treatment to ensure that the gallium oxide microwire 1 completely falls off from the second substrate into the absolute ethyl alcohol solution.

Specifically, 5ml of absolute ethyl alcohol can be measured by using a 10ml measuring cylinder and put into a beaker with 20ml of scales, the second substrate on which the gallium oxide microwire 1 grows is put into the measured absolute ethyl alcohol, and ultrasonic treatment is carried out on the absolute ethyl alcohol, so that the gallium oxide microwire 1 completely falls off from the second substrate to the absolute ethyl alcohol solution.

Step 2, transferring the gallium oxide microwire 1 onto a first substrate 2, wherein the first substrate 2 comprises n⁺SiC substrate layer 21 and at n⁺N on SiC substrate layer 21^-SiC substrate layer 22.

Specifically, an absolute ethanol solution mixed with the gallium oxide microwire 1 is sucked onto the first substrate.

In one embodiment, 1ml of the uniformly mixed gallium oxide microwire anhydrous ethanol solution is pipetted onto the first substrate 2 with a glue dropper, and the ethanol is allowed to evaporate naturally, thereby leaving the gallium oxide microwire 1 on the first substrate 2.

Preferably, n⁺The thickness of the SiC substrate layer 21 is 180-375 mu m, n^-The thickness of the SiC substrate layer is 0.5-11 mu m. The thickness of the n-SiC substrate layer is 0.5-11 microns, so that the defect density of the n-SiC substrate layer can be prevented from being too high, and the performance of a device is prevented from being influenced.

Preferably, n⁺The doping concentration range of the SiC substrate layer 21 is 1E 18-1E 19, n^-The doping concentration range of the SiC substrate layer is 1E 15-1E 17.

And 3, annealing the gallium oxide microwire 1 and the first substrate 2 in inert gas.

Specifically, under the conditions that the inert gas is nitrogen, the annealing temperature is 100-200 ℃, and the annealing time is 10-60 min, the gallium oxide microwire 1 and the first substrate 2 are annealed, so that the interface of the gallium oxide microwire 1 and the first substrate 2 is in close contact.

And 4, preparing a source electrode 3 and a drain electrode 4 at two ends of the gallium oxide microwire 1.

And 4.1, spin-coating a photoresist on the first substrate, and then heating and drying.

Specifically, a resist is spin-coated by a spin coater at, for example, 3500rpm, and then heated and dried using a heating table for, for example, 4 min.

And 4.2, forming an electrode pattern through exposure and development.

Specifically, the electrode pattern is formed through exposure and development, wherein the developing solution is formed by mixing tetramethylammonium hydroxide solution and deionized water, and the developing time is 20-60 s.

In one embodiment, the electrode pattern is exposed and developed by a laser direct writing lithography machine, the exposure time of the lithography machine is 3-10 s, and the light intensity is 2mW/cm²The developing solution is formed by mixing 10ml of tetramethylammonium hydroxide solution (containing 25 mass percent of water) and 330ml of deionized water, and the developing time is 20 s.

And 4.3, preparing a source electrode 3 and a drain electrode 4 at two ends of the gallium oxide microwire 1 by adopting an electron beam evaporation coating method.

Specifically, a source electrode 3 and a drain electrode 4 made of titanium/gold are prepared at both ends of a gallium oxide microwire 1 by an electron beam evaporation coater.

Preferably, the thickness of titanium is 4nm and the thickness of gold is 60 nm.

And 5, preparing a gate electrode 5 on one surface of the first substrate 2 far away from the gallium oxide microwire 1.

Preferably, the material of the gate electrode 5 is Ni/Ag.

Referring to fig. 3, 4, 5 and 6, fig. 3 is a SEM image of the device, fig. 3 shows that gallium oxide microwires with excellent quality are selected and the channel is clearly visible, the device contact is good, fig. 4 shows that the optical power intensity is 244.8 μ W · cm^-2Under 254nm ultraviolet light, the relationship between the current between source flows corresponding to the device and the voltage between the source and the drain can be seen through figure 4 that the device shows good schottky contact, and figure 5 shows that the light power intensity is 244.8 muW cm^-2Under 254nm ultraviolet light, when Vds is-2V, the source flow current changes with time, and it can be seen from fig. 5 that the device can stably detect the ultraviolet light, and fig. 6 is the optical workThe rate intensity was 244.8. mu.W.cm^-2The graph of photocurrent versus time under 254nm ultraviolet light shows that the response speed of the device is high as can be seen from fig. 6.

According to the invention, the gallium oxide microwire is prepared on SiC, so that the prepared photoelectric detector uses the epitaxial lightly doped SiC substrate layer as a photosensitive substrate, and a one-dimensional gallium oxide microwire and a three-dimensional SiC heterostructure are prepared, thereby having better ultraviolet light detection capability.

The SiC substrate used by the invention has good heat dissipation capability and high pressure resistance capability, not only meets the high pressure driving requirement of gallium oxide, but also makes up the defect of insufficient heat dissipation of gallium oxide.

The preparation method of the photoelectric detector provided by the invention has the advantages of simple preparation process, mature testing technology and low manufacturing cost, and is very beneficial to the future commercial popularization.

The photoelectric detector of the silicon carbide/gallium oxide micron line of the mixed-dimensional system prepared by the invention is suitable for detecting ultraviolet wave bands.

Example two

Referring to fig. 2, the present embodiment provides a photodetector of SiC-based gallium oxide microwire based on the above embodiments, the photodetector includes:

a first substrate 2, the first substrate 2 comprising n⁺SiC substrate layer 21 and at n⁺N on SiC substrate layer 21^-A SiC substrate layer 22;

a gallium oxide microwire 1 on a first substrate 2;

a source electrode 3 and a drain electrode 4 located on the first substrate 2 and at both ends of the gallium oxide microwire 1;

and a gate electrode 5 on a lower surface of the first substrate 2.

According to the invention, the gallium oxide microwire is prepared on SiC, so that the prepared photoelectric detector uses the epitaxial lightly doped SiC substrate layer as a photosensitive substrate, and a one-dimensional gallium oxide microwire and a three-dimensional SiC heterostructure are prepared, thereby having better ultraviolet light detection capability.

The SiC substrate used by the invention has good heat dissipation capability and high pressure resistance capability, not only meets the high pressure driving requirement of gallium oxide, but also makes up the defect of insufficient heat dissipation of gallium oxide.

In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic data point described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.