A process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide

Abstract

The present invention discloses a process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, belonging to the technical field of semiconductor materials. The process comprises the following steps: (1) replacing the air in the reaction tube with hydrogen; placing an indium antimonide substrate in the reaction tube, and uniformly placing small-particle-size indium grains on the surface of the indium antimonide substrate; (2) heating the indium antimonide substrate and the indium grains to melt the indium grains and uniformly attach them to the surface of the indium antimonide substrate; (3) heating the liquid arsenic tribromide storage tank to vaporize the liquid arsenic tribromide and introducing it into the reaction tube through hydrogen; (4) heating the reaction tube to cause the small-particle-size indium grains, arsenic tribromide, and hydrogen to react to form indium arsenide on the indium antimonide substrate; (5) cooling to obtain the finished indium arsenide epitaxial thin film wafer. The present invention uses liquid arsenic tribromide as a raw material, reduces the dependence on high-purity arsenic as an upstream raw material, and reduces production costs; the thickness of the prepared indium arsenide epitaxial thin film wafer is also significantly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor materials, and specifically relates to a process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide. Background Art

[0002] The molecular formula of indium antimonide is InSb, and its molecular weight is 236.578. It is a compound semiconductor with a metallic luster, a zinc blende structure, a direct transition type energy band structure, a melting point of 525 °C, and a low dislocation density of single crystal materials. At room temperature, the band gap width is 0.18 electron volts, which is a super-narrow band gap semiconductor material. The corresponding wavelength of the electro-excited light wave is 5.3 microns, which exactly meets the detection wavelength requirements of mid-wave infrared radiation signals, and it is an infrared detector material with excellent performance. The chemical formula of indium arsenide is InAs, which is a compound semiconductor material. It is a silver-gray solid at room temperature, has a zinc blende type crystal structure, a lattice constant of 0.6058 nm, a direct transition energy band structure, a band gap width (300K) of 0.45 eV, and has characteristics such as a high saturated electron drift velocity, a high photoelectric conversion efficiency, and a super-narrow band gap width. It is an ideal material for manufacturing Hall devices and magnetoresistive devices, and also has a wide range of applications in the field of infrared optical devices.

[0003] Both indium antimonide and indium arsenide are semiconductor materials with similar energy band structures and similar band gap widths (0.18 eV and 0.45 eV respectively). They both have characteristics such as a high saturated electron drift velocity, a high photoelectric conversion efficiency, and a super-narrow band gap width, and are all new-generation infrared semiconductor base materials. Epitaxially growing indium arsenide thin film wafers on an indium antimonide substrate can obtain semiconductor composite materials with special properties. Existing methods for epitaxially growing indium arsenide thin film wafers on an indium antimonide substrate mostly use high-purity indium as a raw material, with high production costs, low reaction efficiency, and the resulting indium arsenide thin film is relatively thin, only about 10 μm. Summary of the Invention

[0004] Based on the above technical problems, the present invention proposes a process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, which uses a device for synthesizing indium arsenide epitaxial thin film wafers with arsenic tribromide. The device includes a reaction tube, a high-pressure hydrogen gas storage tank, and a liquid arsenic tribromide storage tank;

[0007] The high-pressure hydrogen gas storage tank is connected to the inlet end of the reaction tube through a hydrogen gas delivery pipeline, and the liquid arsenic tribromide storage tank is connected to the hydrogen gas delivery pipeline through an arsenic tribromide gas delivery pipeline; a first heating element is provided outside the liquid arsenic tribromide storage tank;

[0008] A second heating element is provided outside the reaction tube, a bracket is provided inside the reaction tube, a third heating element is provided at the bracket, and the outlet end of the reaction tube is connected to an exhaust gas output pipeline;

[0009] This process includes the following steps:

[0010] (1) Hydrogen in the high-pressure hydrogen storage tank is transported through a hydrogen transport pipeline into the reaction tube to completely displace the air in the reaction tube; the indium antimonide substrate is placed on the bracket, and small-particle-size indium grains are placed on the surface of the indium antimonide substrate;

[0011] (2) Use the third heating element to heat the indium antimonide substrate and the indium grains, causing the indium grains to melt and uniformly adhere to the surface of the indium antimonide substrate;

[0012] (3) Heat the liquid arsenic tribromide storage tank through the first heating element to vaporize the liquid arsenic tribromide in the liquid arsenic tribromide storage tank; the vaporized arsenic tribromide is introduced into the reaction tube through hydrogen;

[0013] (4) Heat the reaction tube through the second heating element to 400 - 450 °C, causing the small-particle-size indium grains, arsenic tribromide, and hydrogen to react and form indium arsenide on the indium antimonide substrate; the hydrogen bromide generated by the reaction is discharged through the exhaust gas output pipeline;

[0014] (5) After the reaction is completed, continuously introduce room-temperature hydrogen into the reaction tube and cool it to room temperature to obtain a finished indium arsenide epitaxial thin film wafer.

[0015] Preferably, the reaction tube is arranged horizontally, and the inlet end and the outlet end of the reaction tube are respectively arranged at both ends of the reaction tube; the bracket is arranged at the middle position of the bottom wall of the reaction tube.

[0016] Preferably, a heat-insulating material is provided outside the reaction tube, and the heat-insulating material is made of ceramic fiber; the second heating element is arranged between the heat-insulating material and the outer wall of the reaction tube.

[0017] Preferably, in step (1): the indium antimonide substrate is contained in a quartz boat, and the small-particle-size indium grains are smeared on the upper surface of the indium antimonide substrate.

[0018] Preferably, the particle size of the small-particle-size indium grains is 0.8 - 1 micron, and the dosage of the small-particle-size indium grains is 50 - 60 micrograms.

[0019] Preferably, in step (2): control the third heating element to heat to 200 - 250 °C.

[0020] Preferably, in step (3): control the heating of the arsenic tribromide storage tank to 220 - 250 °C.

[0021] Preferably, in step (4): while heating the reaction tube, it is necessary to maintain the system pressure inside the reaction tube at 1 - 1.2 Mpa; and continuously react at 400 - 450 °C for 2 - 3 hours.

[0022] Preferably, in step (4): the waste gas output pipeline is also respectively connected to a waste liquid discharge pipe and a waste gas discharge pipe. The waste liquid discharge pipe is connected to a waste liquid storage tank, and the waste gas discharge pipe is connected to a waste gas treatment system;

[0023] The waste gas in the reaction tube is discharged through the waste gas output pipeline. During the discharge process, arsenic tribromide in the waste gas condenses into a liquid state and flows back to the waste liquid storage tank for storage through the waste liquid discharge pipe. Hydrogen bromide gas and hydrogen gas in the waste gas are transported to the waste gas treatment system through the waste gas discharge pipe for incineration or reuse treatment.

[0024] Preferably, in step (5): the thickness of the indium arsenide epitaxial thin film wafer is 50 - 55 μm.

[0025] The beneficial technical effects of the present invention are:

[0026] The present invention uses arsenic tribromide mixed with hydrogen gas to synthesize an indium arsenide epitaxial thin film wafer on the surface of an indium antimonide substrate by melting high-purity indium, which greatly shortens the reaction time, reduces the reaction temperature, and improves the reaction efficiency; moreover, using liquid arsenic tribromide as a raw material, the purification difficulty of liquid arsenic tribromide is much smaller than that of high-purity arsenic, and its price is also much lower than that of high-purity arsenic. Therefore, using arsenic tribromide as a raw material not only reduces the dependence on high-purity arsenic as the upstream raw material, but also reduces the production cost. The process of the present invention can also increase the thickness of the prepared indium arsenide epitaxial thin film wafer. Through observation and testing, the thickness of the indium arsenide epitaxial thin film wafer synthesized by the present invention reaches 50 μm, which is significantly thicker than the about 10 μm thin indium arsenide film synthesized by the conventional method. Description of the Drawings

[0027] Figure 1 It is a process flow chart of the present invention for synthesizing an indium arsenide epitaxial thin film wafer using arsenic tribromide;

[0028] Figure 2 It is a schematic diagram of the device structure principle for synthesizing an indium arsenide epitaxial thin film wafer using arsenic tribromide adopted by the present invention;

[0029] Figure 3 It is a micrograph of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention;

[0030] Figure 4 It is an XRD scan diagram of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention;

[0031] Figure 5 It is a PL room temperature spectrum diagram of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention.

[0032] In the figure: 1 - reaction tube, 2 - high-pressure hydrogen storage tank, 3 - liquid arsenic tribromide storage tank, 4 - hydrogen delivery pipeline, 5 - pressure pump, 6 - arsenic tribromide gas delivery pipeline, 7 - first heating element, 8 - second heating element, 9 - ceramic fiber sheet, 10 - bracket, 11 - waste gas output pipeline, 12 - waste liquid discharge pipe, 13 - waste gas discharge pipe, 14 - waste liquid storage tank, 15 - third heating element. Specific implementation mode

[0033] An indium arsenide epitaxial thin film wafer can be grown epitaxially on an indium antimonide substrate to obtain a semiconductor composite material with specific properties (such as increasing the transition wavelength to 2.3 μm). Based on this, the present invention innovatively proposes a process for synthesizing an indium arsenide epitaxial thin film wafer using arsenic tribromide. The quartz boat containing the indium antimonide substrate is placed in the middle of the reaction tube, and high-purity hydrogen is used to carry gaseous arsenic tribromide to react with the high-purity indium in the thin layer on the indium antimonide substrate to synthesize an indium arsenide epitaxial thin film product.

[0034] The present invention will be further described below in conjunction with specific embodiments.

[0035] Embodiment 1

[0036] A process for synthesizing an indium arsenide epitaxial thin film wafer using arsenic tribromide, adopting a device for synthesizing an indium arsenide epitaxial thin film wafer using arsenic tribromide, as Figure 2 shown. The device includes a reaction tube 1, a high-pressure hydrogen storage tank 2 and a liquid arsenic tribromide storage tank 3. The high-pressure hydrogen storage tank 2 is connected to the inlet end of the reaction tube 1 through a hydrogen delivery pipeline 4, and a pressure pump 5 is provided on the hydrogen delivery pipeline 4. The liquid arsenic tribromide storage tank 3 is connected to the hydrogen delivery pipeline 4 through an arsenic tribromide gas delivery pipeline 6. A first heating element 7 is provided outside the liquid arsenic tribromide storage tank 3. A second heating element 8 is provided outside the reaction tube 1, and a heat insulation material is provided outside the reaction tube 1. The heat insulation material uses a ceramic fiber sheet 9 to play a role in isolating high temperature. The second heating element 8 is provided between the heat insulation material and the outer wall of the reaction tube. A bracket 10 is provided inside the reaction tube 1. The cross-section of the bracket 10 is T-shaped, and the bracket 10 is provided at the middle position of the bottom wall of the reaction tube 1. A third heating element 15 is provided at the bracket 10. The reaction tube 1 is arranged horizontally, and the inlet end and the outlet end of the reaction tube 1 are respectively provided at both ends of the reaction tube 1. The outlet end of the reaction tube 1 is connected to a waste gas output pipeline 11. The waste gas output pipeline 11 is also respectively connected to a waste liquid discharge pipe 12 and a waste gas discharge pipe 13. The waste liquid discharge pipe 12 is connected to a waste liquid storage tank 14, and the waste gas discharge pipe 13 is connected to a waste gas treatment system.

[0037] As Figure 1 shown, the process includes the following steps:

[0038] (1) The hydrogen in the high-pressure hydrogen storage tank 2 is transported through the hydrogen transport pipeline 4 into the reaction tube 1 to completely displace the air in the reaction tube 1. Place the indium antimonide substrate in a quartz boat, and place the quartz boat on the bracket 10. And quickly place high-purity small-sized indium grains on the upper surface of the indium antimonide substrate. The particle size of the small-sized indium grains is 1 micron, and the dosage of the small-sized indium grains is 50 micrograms.

[0039] (2) Heat the reaction tube 1 through the third heating element 15, first heat it to about 250 °C, so that the high-purity small-sized indium grains are completely melted and adhere to the surface of the indium antimonide substrate.

[0040] (3) Heat the liquid arsenic tribromide storage tank 3 through the first heating element 7, slowly heat the liquid arsenic tribromide storage tank to 220 °C, so that the liquid arsenic tribromide in the liquid arsenic tribromide storage tank is vaporized. The vaporized arsenic tribromide is introduced into the reaction tube 1 through hydrogen.

[0041] (4) Continue to heat the reaction tube through the second heating element 8 to 400 °C, and keep the system pressure in the reaction tube at 1 Mpa. At this temperature and pressure, the melted small-sized indium grains, arsenic tribromide and hydrogen continuously undergo the following disproportionation chemical reaction on the surface of the indium antimonide substrate, and indium arsenide is formed on the indium antimonide substrate. The chemical reaction formula is as follows:

[0042] 2AsBr3 + 3H2 + 2In = 2InAs + 6HBr;

[0043] The continuous reaction time is 2.5 hours. The hydrogen bromide generated by the reaction is discharged through the waste gas output pipeline 11. During the discharge process, the arsenic tribromide in the waste gas condenses into a liquid state and flows back to the waste liquid storage tank 14 for storage through the waste liquid discharge pipe 12. The hydrogen bromide gas and hydrogen in the waste gas are transported through the waste gas discharge pipe 13 to the waste gas treatment system for incineration or recycling treatment.

[0044] (5) After the reaction is completed, continuously introduce normal-temperature hydrogen into the reaction tube 1, cool it to room temperature, take out the product, and obtain the indium arsenide epitaxial thin film wafer finished product.

[0045] Figure 3 This is the micrograph of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention. It can be seen from the figure that the thickness of the indium arsenide epitaxial thin film wafer synthesized by the present invention is 50 μm. Figure 4 This is the XRD scan pattern of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention. Figure 4 It shows the crystal orientation distribution of the indium arsenide epitaxial thin film wafer, and the (111) crystal orientation is the most concentrated. Figure 5 This is the PL room temperature spectrum of the indium arsenide epitaxial thin film wafer prepared in Example 1 of the present invention. Figure 5It is shown that the characteristic spectral line at a wavelength of 2.3 μm unique to indium arsenide appears in the wafer on which the thin film is formed.

[0046] Example 2

[0047] A process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, and an apparatus for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide. The structure of this apparatus is the same as that in Example 1. This process includes the following steps:

[0048] (1) Hydrogen in the high-pressure hydrogen storage tank 2 is transported through the hydrogen transport pipeline 4 into the reaction tube 1 to completely displace the air in the reaction tube 1. The indium antimonide substrate is placed in a quartz boat, and the quartz boat is placed on a bracket. High-purity small-sized indium grains are quickly placed on the upper surface of the indium antimonide substrate. The particle size of the small-sized indium grains is 0.8 μm, and the amount of the small-sized indium grains used is 60 μg.

[0049] (2) The reaction tube 1 is heated by the third heating element 15, first heated to about 200 °C, so that the high-purity small-sized indium grains are completely melted and adhere to the surface of the indium antimonide substrate.

[0050] (3) The liquid arsenic tribromide storage tank 3 is heated by the first heating element 7, and the liquid arsenic tribromide storage tank is slowly heated to 250 °C to vaporize the liquid arsenic tribromide in the liquid arsenic tribromide storage tank. The vaporized arsenic tribromide is introduced into the reaction tube 1 through hydrogen.

[0051] (4) The reaction tube is continuously heated by the second heating element 8 to 450 °C, and the system pressure inside the reaction tube is maintained at 1.2 Mpa. At this temperature and pressure, the melted small-sized indium grains, arsenic tribromide, and hydrogen continuously undergo the following disproportionation chemical reaction on the surface of the indium antimonide substrate to form indium arsenide on the indium antimonide substrate. The chemical reaction formula is as follows:

[0052] 2AsBr3 + 3H2 + 2In = 2InAs + 6HBr;

[0053] The continuous reaction time is 2 hours. The hydrogen bromide generated by the reaction is discharged through the waste gas output pipeline 11. During the discharge process, the arsenic tribromide in the waste gas condenses into a liquid state and is refluxed to the waste liquid storage tank 14 for storage through the waste liquid discharge pipe 12. The hydrogen bromide gas and hydrogen in the waste gas are transported to the waste gas treatment system through the waste gas discharge pipe 13 for incineration or recycling treatment.

[0054] (5) After the reaction is completed, normal-temperature hydrogen is continuously introduced into the reaction tube 1, cooled to room temperature, and the product is taken out to obtain the finished indium arsenide epitaxial thin film wafer.

[0055] Example 3

[0056] A process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, and an apparatus for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide. The structure of this apparatus is the same as that in Embodiment 1. This process includes the following steps:

[0057] (1) Hydrogen in the high-pressure hydrogen storage tank 2 is transported through the hydrogen transport pipeline 4 into the reaction tube 1 to completely displace the air in the reaction tube 1. The indium antimonide substrate is loaded in a quartz boat, and the quartz boat is placed on a bracket. And high-purity small-sized indium grains are quickly placed on the upper surface of the indium antimonide substrate. The particle size of the small-sized indium grains is 0.9 micrometers, and the dosage of the small-sized indium grains is 55 micrograms.

[0058] (2) The reaction tube 1 is heated by the third heating element 15, first heated to about 220 °C, so that the high-purity small-sized indium grains are completely melted and adhere to the surface of the indium antimonide substrate.

[0059] (3) The liquid arsenic tribromide storage tank 3 is heated by the first heating element 7, and the arsenic tribromide storage tank is slowly heated to 230 °C to vaporize the liquid arsenic tribromide in the liquid arsenic tribromide storage tank. The vaporized arsenic tribromide is introduced into the reaction tube 1 through hydrogen.

[0060] (4) The reaction tube is continuously heated by the second heating element 8 to 430 °C, and the system pressure inside the reaction tube is maintained at 1 Mpa. At this temperature and pressure, the melted small-sized indium grains, arsenic tribromide and hydrogen continuously undergo the following disproportionation chemical reaction on the surface of the indium antimonide substrate to form indium arsenide on the indium antimonide substrate. The chemical reaction formula is as follows:

[0061] 2AsBr3 + 3H2 + 2In = 2InAs + 6HBr;

[0062] The continuous reaction time is 3 hours. The hydrogen bromide generated by the reaction is discharged through the waste gas output pipeline 11. During the discharge process, the arsenic tribromide in the waste gas condenses into a liquid state and is refluxed to the waste liquid storage tank 14 for storage through the waste liquid discharge pipe 12. The hydrogen bromide gas and hydrogen in the waste gas are transported to the waste gas treatment system through the waste gas discharge pipe 13 for incineration or recycling treatment.

[0063] (5) After the reaction is completed, normal-temperature hydrogen is continuously introduced into the reaction tube 1, cooled to room temperature, and the product is taken out to obtain the finished indium arsenide epitaxial thin film wafer.

[0064] For the parts not described above, the existing technology can be adopted or borrowed to achieve.

[0065] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirits of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, characterized in that: A device for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide, the device comprising a reaction tube, a high-pressure hydrogen storage tank and a liquid arsenic tribromide storage tank; The high-pressure hydrogen storage tank is connected to the inlet end of the reaction tube via a hydrogen delivery pipeline, and the liquid arsenic tribromide storage tank is connected to the hydrogen delivery pipeline via an arsenic tribromide gas delivery pipeline; a first heating element is provided on the outer side of the liquid arsenic tribromide storage tank; A second heating element is provided on the outside of the reaction tube, a bracket is provided on the inside of the reaction tube, a third heating element is provided on the bracket, and an outlet end of the reaction tube is connected to an exhaust gas output pipe; The process includes the following steps: (1) Hydrogen in a high-pressure hydrogen storage tank is transported to a reaction tube through a hydrogen delivery pipeline to completely replace the air in the reaction tube; an indium antimonide substrate is placed on a bracket, and indium particles are placed on the surface of the indium antimonide substrate; (2) using a third heating element to heat the indium antimonide substrate and the indium particles, so that the indium particles melt and evenly adhere to the surface of the indium antimonide substrate; (3) heating the liquid arsenic tribromide storage tank by a first heating element to vaporize the liquid arsenic tribromide in the liquid arsenic tribromide storage tank; introducing the vaporized arsenic tribromide into the reaction tube by hydrogen; (4) heating the reaction tube to 400-450° C. by a second heating element, so that the indium particles, arsenic tribromide, and hydrogen react to form indium arsenide on the indium antimonide substrate; the hydrogen bromide produced by the reaction is discharged through an exhaust gas output pipe; (5) After the reaction is completed, hydrogen gas at room temperature is continuously introduced into the reaction tube and cooled to room temperature to obtain a finished indium arsenide epitaxial thin film wafer.

2. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, wherein: The reaction tube is arranged horizontally, and the inlet and outlet ends of the reaction tube are respectively arranged at both ends of the reaction tube; the bracket is arranged at the middle position of the bottom wall of the reaction tube.

3. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: A heat insulating material is arranged on the outside of the reaction tube, and the heat insulating material is made of ceramic fiber; the second heating element is arranged between the heat insulating material and the outer wall of the reaction tube.

4. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (1): the indium antimonide substrate is placed in a quartz boat, and the indium particles are smeared on the upper surface of the indium antimonide substrate.

5. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 4, characterized in that: The particle size of the indium particles is 0.8-1 micrometer, and the amount of the indium particles used is 50-60 micrograms.

6. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (2): the third heating element is controlled to heat to 200-250°C.

7. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (3): the arsenic tribromide storage tank is controlled to be heated to 220-250°C.

8. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (4): while heating the reaction tube, the system pressure in the reaction tube needs to be maintained at 1-1.2 MPa; and the reaction is continued at 400-450° C. for 2-3 hours.

9. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (4): the exhaust gas output pipe is further connected to the waste liquid discharge pipe and the exhaust gas discharge pipe, the waste liquid discharge pipe is connected to the waste liquid storage tank, and the exhaust gas discharge pipe is connected to the exhaust gas treatment system; The waste gas in the reaction tube is discharged through the waste gas output pipe. During the discharge process, the arsenic tribromide in the waste gas is condensed into liquid and returned to the waste liquid storage tank through the waste liquid discharge pipe for storage. The hydrogen bromide gas and hydrogen in the waste gas are transported to the waste gas treatment system through the waste gas discharge pipe for incineration or reuse.

10. The process for synthesizing indium arsenide epitaxial thin film wafers using arsenic tribromide according to claim 1, characterized in that: In step (5): the thickness of the indium arsenide epitaxial thin film wafer is 50-55 μm.

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