Halogen vapor phase epitaxial growth system and use method thereof

Abstract

The invention discloses a halide vapor phase epitaxial growth system and a use method thereof, and belongs to the technical field of semiconductor materials, the halide vapor phase epitaxial growth system comprises a quartz tube body, a metal gallium chamber located in the quartz tube body, a ventilation pipeline, a substrate and three baffles, the three baffles are sequentially arranged in the quartz tube body at intervals and divide the quartz tube body into four cavities, gas is introduced into the ventilation pipeline, and the gallium metal cavity is located in the third cavity in the gas flow direction and used for containing gallium metal. According to the growth system provided by the invention, the three baffles are arranged in the quartz tube body, so that impurity deposition on the inner wall of the chamber and the GaClx outlet tube is effectively reduced, the influence on the growth stability and uniformity of a gallium oxide epitaxial film due to the existence of by-product impurities is avoided, the cleaning cost of the chamber is reduced, and the production efficiency is improved. And the thickness difference between the edge and the central position of the epitaxial film is ensured to be within 10%.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor materials, and more particularly to a halide vapor phase epitaxial growth system and a method for using the same. Background Art

[0002] As a fourth-generation semiconductor material, Ga2O3 has great potential in the application of power electronic devices. There are many methods for growing Ga2O3 epitaxial films, such as metalorganic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), and halide vapor phase epitaxy (HVPE). Since the critical breakdown electric field strength is related to the thickness of the epitaxial layer, growing thick Ga2O3 epitaxial films is the key to fabricating high breakdown voltage power devices. Halide vapor phase epitaxy has an extremely high growth rate, which has attracted extensive attention and research.

[0003] Since the chamber size required for preparing 4-inch Ga2O3 epitaxial films is larger, the equipment cost is higher, the cleaning cost and difficulty are also greater, and the uniformity of the epitaxial films needs to be further improved.

[0004] As Figure 1 shown, the gas flow direction of the horizontal halide vapor phase epitaxial system is horizontal. The whole system consists of six temperature zones. The low-temperature zone consists of temperature zones 1, 2, and 3. The basic reaction principle is Ga + HCL → GaCl + H2, Ga + HCL → GaCl3 + H 2， for controlling the generation of gallium chloride; the high-temperature zone consists of temperature zones 4, 5, and 6. The basic reaction principle is GaCl + O2 → Ga2O3 + Cl2, GaCl3 + O2 → Ga2O3 + Cl2, for the reaction of gallium chloride with oxygen to generate gallium oxide. During the experimental growth, the entire reaction chamber and the substrate need to be maintained at a high temperature. Due to the diffusion of various gases, the high environmental temperature will cause gallium oxide to grow not only on the substrate but also on the inner wall of the entire reaction chamber, causing pollution to the entire chamber and thus affecting the growth of the epitaxial film. And there is a phenomenon of reflux of reaction by-products, which will cause pollution to the entire chamber and seriously affect the crystallization quality of the thin film. Summary of the Invention

[0005] In order to solve the deficiencies of the above technical solutions, the purpose of the present invention is to provide a halide vapor phase epitaxial growth system and a method for using the same.

[0006] The purpose of the present invention is achieved by the following technical solutions.

[0007] A halide vapor phase epitaxial growth system includes a quartz tube body, a gallium metal chamber located within the quartz tube body, a gas supply pipeline, a substrate, and three baffles. The three baffles are sequentially arranged at intervals within the quartz tube body, dividing the quartz tube body into four chambers. A gas flows through the gas supply pipeline. The gallium metal chamber is located in the third chamber along the gas flow direction and is used for placing gallium metal. The gas supply pipeline includes a first gas supply pipeline, a second gas supply pipeline, and a third gas supply pipeline. The first gas supply pipeline, the second gas supply pipeline, and the third gas supply pipeline respectively enter the quartz tube body from one end of the quartz tube body. The second gas supply pipeline sequentially passes through the three baffles, and its gas outlet faces the substrate located in the fourth chamber along the gas flow direction. The first gas supply pipeline sequentially passes through two of the baffles, and its end is located within the gallium metal chamber, with the gas outlet facing the gallium metal. The third gas supply pipeline sequentially passes through two of the baffles, the gallium metal chamber, and the third baffle, and its gas outlet faces the substrate located in the fourth chamber.

[0008] In the above technical solution, a gallium boat and a shielding baffle located above the gallium boat are arranged within the gallium metal chamber, and the gallium metal is placed within the gallium boat.

[0009] In the above technical solution, nozzles are arranged at the gas outlets of the second gas supply pipeline and the third gas supply pipeline.

[0010] In the above technical solution, the first gas supply pipeline, the second gas supply pipeline, and the third gas supply pipeline are arranged in parallel at intervals. Hydrogen chloride gas and a carrier gas flow through the first gas supply pipeline. Oxygen gas and a carrier gas flow through the second gas supply pipeline. Only a carrier gas flows through the third gas supply pipeline.

[0011] In the above technical solution, the carrier gas is nitrogen.

[0012] In the above technical solution, the baffles are circular baffles.

[0013] In the above technical solution, a substrate is placed within the fourth chamber for deposition. The bottom of the substrate is mounted on a ceramic tray, and a graphite rod is mounted on one end surface thereof for feeding the substrate and the ceramic tray into or taking them out of the quartz tube body.

[0014] Another aspect of the present invention further includes a method for using a halide vapor phase epitaxial growth system, including the following steps

[0015] Step 1, before the epitaxial work starts, ultrasonically clean the substrate, rinse the cleaning solution and dry it. Then, send the substrate into the growth temperature zone of the quartz tube body through a graphite rod. Place metal gallium particles as the reaction source in the gallium boat of the metal gallium chamber. Close the gas pipeline, evacuate the air, open all pipelines to evacuate the air, then close the first gas pipeline and the second gas pipeline. The third gas pipeline introduces carrier gas nitrogen with a flow rate of 500 sccm to flush the chamber for 5 minutes, and then adjust the carrier gas nitrogen to 600 sccm.

[0016] Step 2, heat up the gallium source temperature zone and the growth temperature zone, and set the reaction pressure until the growth of the gallium oxide epitaxial film starts on the substrate.

[0017] Step 3, after the growth is completed, lower the temperatures of the gallium source temperature zone and the growth temperature zone to room temperature to obtain the gallium oxide epitaxial film.

[0018] In the above technical solution, the metal gallium chamber is located in the gallium source temperature zone.

[0019] In the above technical solution, the substrate is located in the growth temperature zone.

[0020] The advantages and beneficial effects of the present invention are as follows:

[0021] The growth system provided by the present invention is provided with three baffle plates in the quartz tube body. This structure effectively reduces the impurity deposition on the inner wall of the chamber and at the GaClx outlet pipe, avoids affecting the stability and uniformity of the growth of the gallium oxide epitaxial film due to the presence of by-product impurities, reduces the cleaning cost of the chamber, and also ensures that the thickness difference between the edge and the center position of the epitaxial film is within 10%. Description of the Drawings

[0022] Figure 1 It is a schematic structural diagram of the background technology of the present invention.

[0023] Figure 2 It is a schematic structural diagram of Embodiment 1 of the present invention.

[0024] Figures 3 - 7 It is a TEM image of the thickness of the gallium oxide epitaxial film at different points.

[0025] Among them, 1: quartz tube body, 2: metal gallium chamber, 3: substrate, 4: gallium boat, 5: first gas pipeline, 6: second gas pipeline, 7: third gas pipeline, 8: shielding baffle, 9: baffle, 10: nozzle. Detailed Embodiments

[0026] The following further illustrates the technical solution of the present invention with specific embodiments.

[0027] Embodiment 1

[0028] As Figure 2As shown in the figure, a halide vapor phase epitaxial growth system includes a quartz tube body 1, a gallium metal chamber 2 located inside the quartz tube body 1, a gas supply pipeline, a substrate 3, and three baffles 9. The three baffles 9 are sequentially arranged at intervals inside the quartz tube body 1, dividing the quartz tube body 1 into four chambers. The gas supply pipeline is supplied with gas. The gallium metal chamber 2 is located in the third chamber along the gas flow direction and is used to place gallium metal. The gas supply pipeline is horizontally arranged along the length direction of the quartz tube body 1. The gas supply pipeline includes a first gas supply pipeline 5, a second gas supply pipeline 6, and a third gas supply pipeline 7. The first gas supply pipeline 5, the second gas supply pipeline 6, and the third gas supply pipeline 7 respectively enter the quartz tube body 1 from one end of the quartz tube body 1. The second gas supply pipeline 6 sequentially passes through the three baffles 9, and its air outlet is opposite to the substrate 3 located in the fourth chamber along the gas flow direction. The first gas supply pipeline 5 sequentially passes through two of the baffles 9, and its end is located inside the gallium metal chamber 2, and the air outlet is opposite to the gallium metal. The third gas supply pipeline 7 sequentially passes through two of the baffles 9, the gallium metal chamber 2, and the third baffle 9, and its air outlet is located in the fourth chamber. A gallium boat 4 and a shielding baffle 8 located above the gallium boat 4 are arranged inside the gallium metal chamber 2. The shielding baffle 8 can prevent the reaction by-products from flowing back, effectively reducing the impurity deposition on the inner wall of the chamber and at the GaClx outlet pipe, avoiding affecting the stability and uniformity of the growth of the gallium oxide epitaxial film due to the presence of by-product impurities, and reducing the cleaning cost of the chamber.

[0029] Further, the first gas supply pipeline 5, the second gas supply pipeline 6, and the third gas supply pipeline 7 are arranged at intervals and in parallel. The first gas supply pipeline 5 is supplied with hydrogen chloride gas and a carrier gas. The second gas supply pipeline 6 is supplied with oxygen gas and a carrier gas. The third gas supply pipeline 7 is supplied with a carrier gas. The carrier gas is nitrogen, which is used to send the gallium chloride generated by the reaction of hydrogen chloride and gallium metal to the fourth chamber (growth temperature zone) for reaction. Sprayers 10 are arranged at the air outlets of the second gas supply pipeline 6 and the third gas supply pipeline 7 to mix the gases at the air outlets evenly.

[0030] Further, the baffle 9 is a circular baffle 9, which can effectively prevent the reaction by-product impurities from polluting the quartz tube body 1, has no influence on the growth of the gallium oxide epitaxial film, and can control the consistency of the thickness of the gallium oxide epitaxial film.

[0031] Further, a substrate 3 is placed in the fourth chamber for deposition. The bottom of the substrate 3 is installed on a ceramic tray, and a graphite rod is installed on one end surface (close to the outlet end of the quartz tube body 1) to send the substrate 3 and the ceramic tray into or out of the quartz tube body 1.

[0032] Example 2

[0033] This embodiment provides a method for using the halide vapor phase epitaxial growth system described in Embodiment 1, including the following steps

[0034] Step 1: Using c-plane sapphire as the substrate 3 to grow a gallium oxide epitaxial layer. Before the epitaxial work starts, ultrasonically clean the substrate 3 successively with anhydrous ethanol and acetone. After taking out the substrate 3, rinse it with deionized water and dry it with a nitrogen gun. Then, send the substrate 3 into the growth temperature zone of the quartz tube body 1 through a graphite rod. Place metal gallium particles as the reaction source in the gallium boat 4 of the metal gallium chamber 2. Close the gas pipeline, evacuate the air, open all pipelines to evacuate the air, then close the first gas pipeline 5 and the second gas pipeline 6. The third gas pipeline 7 is introduced with carrier gas nitrogen with a flow rate of 500 sccm to flush the chamber for 5 minutes, and then the carrier gas nitrogen is adjusted to 600 sccm.

[0035] Step 2: Heat up the gallium source temperature zone and the growth temperature zone, and set the reaction pressure until the growth of the gallium oxide epitaxial film starts on the substrate 3.

[0036] Step 3: After the growth is completed, slowly cool the gallium source temperature zone and the growth temperature zone to room temperature to obtain the gallium oxide epitaxial film.

[0037] Furthermore, the metal gallium chamber is located in the gallium source temperature zone, and the substrate is located in the growth temperature zone.

[0038] There is Figures 3 - 6 It can be seen that the thickness distribution of the gallium oxide epitaxial film prepared in this embodiment is uniform at different points, and the error is within 10%.

[0039] The above has made an exemplary description of the present invention. It should be noted that without departing from the core of the present invention, any simple deformation, modification, or equivalent replacement that can be made by those skilled in the art without creative labor falls within the protection scope of the present invention.

Claims

1. A halide vapor phase epitaxial growth system, characterized in that, It includes a quartz tube body, a gallium metal chamber located inside the quartz tube body, a gas venting pipeline, a substrate, and three baffles. The three baffles are arranged at intervals in the quartz tube body in sequence, dividing the quartz tube body into four chambers. A gas is passed through the gas venting pipeline. The gallium metal chamber is located in the third chamber along the gas flow direction and is used for placing gallium metal. The gas venting pipeline includes a first gas venting pipeline, a second gas venting pipeline, and a third gas venting pipeline. The first gas venting pipeline, the second gas venting pipeline, and the third gas venting pipeline respectively enter the quartz tube body from one end of the quartz tube body. The second gas venting pipeline passes through the three baffles in sequence, and its air outlet is opposite to the substrate located in the fourth chamber along the gas flow direction. The first gas venting pipeline passes through two of the baffles in sequence, and its end is located inside the gallium metal chamber, and the air outlet is opposite to the gallium metal. The third gas venting pipeline passes through two of the baffles, the gallium metal chamber, and the third baffle in sequence, and its air outlet is opposite to the substrate located in the fourth chamber.

2. The halide vapor phase epitaxial growth system according to claim 1, characterized in that, A gallium boat and a shielding baffle located above the gallium boat are arranged inside the gallium metal chamber, and the gallium metal is placed in the gallium boat.

3. The halide vapor phase epitaxial growth system according to claim 1, wherein Sprayers are arranged at the air outlets of the second gas venting pipeline and the third gas venting pipeline.

4. The halide vapor phase epitaxial growth system according to claim 1, characterized in that, The first gas venting pipeline, the second gas venting pipeline, and the third gas venting pipeline are arranged in parallel at intervals. Hydrogen chloride gas and a carrier gas are passed through the first gas venting pipeline. Oxygen gas and a carrier gas are passed through the second gas venting pipeline. Only a carrier gas is passed through the third gas venting pipeline.

5. The halide vapor phase epitaxial growth system according to claim 1, wherein The carrier gas is nitrogen.

6. The halide vapor phase epitaxial growth system according to claim 1, characterized in that, The baffle is a circular baffle.

7. The halide vapor phase epitaxial growth system according to claim 1, wherein, The bottom of the substrate is mounted on a ceramic tray, and a graphite rod is mounted on one end face.

8. The method of using a halide vapor phase epitaxial growth system according to any one of claims 1 to 7, characterized in that, It includes the following steps Step 1, before the epitaxial work starts, the substrate is ultrasonically cleaned, then the cleaning solution is rinsed and dried, and the substrate is sent into the growth temperature zone of the quartz tube body through the graphite rod. Gallium metal particles are placed as a reaction source in the gallium boat in the gallium metal chamber. The gas venting pipeline is closed, and the air is evacuated. After all pipelines are opened and evacuated, the first gas venting pipeline and the second gas venting pipeline are closed. The third gas venting pipeline is passed with a carrier gas nitrogen with a flow rate of 500 sccm to rinse the chamber for 5 min, and then the carrier gas nitrogen is adjusted to 600 sccm. Step 2, the temperature of the gallium source temperature zone and the growth temperature zone is increased, and the reaction pressure is set until the gallium oxide epitaxial film starts to grow on the substrate. Step 3, after the growth is completed, the temperatures of the gallium source temperature zone and the growth temperature zone are reduced to room temperature, and the gallium oxide epitaxial film is obtained.

9. The usage method according to claim 8, wherein, The gallium metal chamber is located in the gallium source temperature zone.

10. The usage method according to claim 8, characterized in that The substrate is located in the growth temperature zone.

Images