Pretreatment method of vapor phase growth equipment and method for preparing thin film of group III-V compounds

Abstract

The present invention provides a pretreatment method for a vapor phase growth device and a method for preparing a III-V compound film. The pretreatment method for the vapor phase growth device includes controlling the top plate temperature of a temperature-controllable top plate to 130-170°C, the base temperature of a rotating base to 600-720°C, the chamber pressure in the reaction chamber to 35-100 mbar, the rotation rate of the rotating base to 6-15 rpm, and providing an aluminum source and a pre-reaction gas source including at least two of a gallium source, an arsenic source, an indium source, and a phosphorus source into the reaction chamber, so that a III-V compound film containing aluminum of a preset thickness can be formed on the inner wall of the reaction chamber of the vapor phase growth device and the exposed surface of the rotating base. The III-V compound film containing aluminum has a strong adsorption capacity for oxygen, can fix particulate matter in the reaction chamber that is not easy to be purged and removed, and provides a good process environment for the subsequent III-V compound film.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a pretreatment method for vapor phase growth equipment and a method for preparing a III-V group compound film. Background Art

[0002] Group III-V compound films are semiconductor materials formed by chemical bonds between Group III and Group V elements in the periodic table. For example, semiconductor materials such as gallium arsenide (GaAs), indium phosphide (InP), aluminum gallium arsenide (AlGaAs), and indium arsenide (InAs) are characterized by wide bandgap, high electron mobility, and good photoelectric properties, and therefore have a wide range of applications in optoelectronics, microwave devices, and high-speed electronic devices.

[0003] In the prior art, before a vapor phase growth reaction is performed in a reaction chamber to prepare a semiconductor thin film, in consideration of the reaction requirements, a non-reactive purge gas (such as nitrogen) needs to be continuously introduced into the reaction chamber through a gas injection device, and at the same time, it needs to be discharged through an exhaust system to replace the air in the reaction chamber and to discharge impurities such as particulate matter in the reaction chamber to prevent them from affecting the performance of the thin film. However, the purge gas introduced into the reaction chamber through a gas injection device has a limited degree of purging of particles adsorbed on the side walls and base of the reaction chamber. Considering the process cycle and efficiency requirements, it cannot be ensured that the impurities in the reaction chamber can be completely removed. Even if the process cycle and efficiency requirements are not taken into consideration, blindly extending the purge time will increase energy consumption and costs.

[0004] In addition, since the vapor phase growth reaction is not only to achieve thin film deposition on the substrate surface on the susceptor, a deposition layer will also be formed on the side walls of the reaction chamber and the non-substrate-bearing area of ​​the susceptor. For the vapor phase growth process of III-V compound thin films, if the reaction chamber is first used to deposit other semiconductor thin films of different composition materials, the deposition layers formed on the chamber walls and the susceptor are likely to be detrimental to its growth process. For example, the components in these deposition layers will precipitate under the process conditions and may affect the quality of the film.

[0005] Moreover, during the vapor phase growth process of the III-V compound thin film in the reaction chamber, the top plate where the gas injection device is located is prone to droplet aggregation and particle deposition, which can easily affect the quality of the semiconductor film.

[0006] Therefore, it is necessary to provide a novel method for preparing a III-V group compound thin film and a pretreatment method for a vapor phase growth device to solve the above-mentioned problems existing in the prior art. Summary of the invention

[0007] The object of the present invention is to provide a pretreatment method for a vapor phase growth device and a method for preparing a III-V compound film using the pretreated vapor phase growth device, which is beneficial to provide a good process environment for the preparation of the III-V compound film and reduce or avoid the adverse effects on the film quality caused by droplet aggregation or particle deposition on the top plate where the gas injection device is located.

[0008] To achieve the above object, the pretreatment method of the vapor phase growth equipment of the present invention comprises the following steps:

[0009] S0: Provide a vapor phase growth device, the vapor phase growth device comprising a reaction chamber, a temperature-controllable top plate disposed on the top of the reaction chamber, a temperature-controllable rotating base disposed in the reaction chamber, and a gas injection device disposed on the temperature-controllable top plate and opposite to the rotating base, the top surface of the rotating base comprising a wafer carrier area, a companion wafer is placed in the wafer carrier area, and the ratio of the diameter of the rotating base to the height of the reaction space in the reaction chamber is 12:1 to 40:1;

[0010] S1: Controlling the top plate temperature of the temperature-controllable top plate to 130-170° C., the base temperature of the rotating base to 600-720° C., the chamber pressure in the reaction chamber to 35-100 mbar, and the rotation speed of the rotating base to 6-15 rpm;

[0011] S2: Providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device to perform a thin film growth reaction until an aluminum-containing III-V compound thin film of a preset thickness is formed on the exposed surface of the inner wall of the reaction chamber and the top surface of the rotating base;

[0012] The reaction gas source includes at least two of a gallium source, an arsenic source, an indium source and a phosphorus source.

[0013] The beneficial effect of the pretreatment method is that in the vapor phase growth equipment provided in step S0, the ratio of the diameter of the rotating base to the height of the reaction space in the reaction chamber is 12:1~40:1, the distance between the temperature-controlled top plate and the rotating base is short, and the top plate temperature of the temperature-controlled top plate is controlled to be 130~170 degrees Celsius and the base temperature of the rotating base is 600~720°C by step S1, which is conducive to forming a reasonable temperature gradient field in the reaction space, reducing or avoiding the consumption of reaction gas and top plate particles caused by the pre-reaction near the temperature-controlled top plate due to the high temperature of the temperature-controlled top plate after the aluminum source and the pre-reaction gas used in step S2 are ejected from the gas injection device. The problem of material deposition is solved; further combined with controlling the rotation rate of the rotating base to be 6-15 rpm, controlling the chamber pressure to be 35-100 mbar, and providing an aluminum source and a pre-reaction gas source including at least two of a gallium source, an arsenic source, an indium source and a phosphorus source into the reaction chamber through step S2 to perform a thin film growth reaction, a III-V compound film containing aluminum of a preset thickness can be formed on the inner wall of the reaction chamber of the vapor phase growth equipment and the exposed surface of the rotating base. The III-V compound film containing aluminum has a strong adsorption capacity for oxygen, can fix particulate matter that is difficult to be purged and removed in the reaction chamber, and provides a good process environment for the subsequent III-V compound film.

[0014] Optionally, before executing step S1, the step further includes performing a dehydration and oxygen removal treatment on the reaction chamber, wherein the deoxygenation treatment includes the following steps:

[0015] Sa1: providing a purge gas into the reaction chamber through the gas injection device, controlling the base temperature of the rotating base to rise to 180-320 degrees Celsius, and controlling the chamber pressure in the reaction chamber to be the same as the chamber pressure in the reaction chamber in step S1;

[0016] Sa2: providing an arsenic source or a phosphorus source into the reaction chamber through the gas injection device, controlling the temperature of the susceptor to rise to a temperature higher than the susceptor temperature in step S1, and then continuing for a preset time.

[0017] Optionally, in step Sa2, the base temperature is controlled to be 10-30° C. higher than the base temperature in step S1, and the preset time is 3-10 minutes.

[0018] Optionally, the height of the reaction space is 15-50 mm, and the height of the reaction space is the height between the bottom surface of the temperature-controllable top plate and the top surface of the rotating base.

[0019] Optionally, in step S2, the preset thickness of the III-V compound film is 2-8 μm.

[0020] Optionally, in step S2, the flow rate of the aluminum source is controlled to 60-180 sccm, and the flow rates of at least two of the following sources are controlled: the flow rate of the gallium source is 15-45 sccm, the flow rate of the arsenic source is 60-450 sccm, the flow rate of the indium source is 400-1200 sccm, and the flow rate of the phosphorus source is 600-1200 sccm.

[0021] Optionally, when the pre-reaction gas source includes a gallium source and an arsenic source, in step S2, the flow rate of the gallium source is controlled to be 15-45 sccm, and the flow rate of the arsenic source is controlled to be 150-450 sccm.

[0022] Optionally, the method further includes controlling the V / III ratio in the mixed gas consisting of the arsenic source and the gallium source to be 30-150.

[0023] Optionally, when the pre-reaction gas source includes an indium source, a phosphorus source and an arsenic source, in step S2, the flow rate of the indium source is controlled to be 400-1200 sccm, the flow rate of the phosphorus source is controlled to be 600-1200 sccm, and the flow rate of the arsenic source is controlled to be 60~180 sccm.

[0024] Optionally, the method further includes controlling the V / III ratio of the mixed gas composed of an indium source, a phosphorus source and an arsenic source to be 60-200.

[0025] Optionally, when the pre-reaction gas source includes a gallium source and an arsenic source, in step S2, the step of providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device for a thin film growth reaction includes controlling the continuous introduction of an arsenic source into the reaction chamber, and alternately introducing a gallium source and an aluminum source into the reaction chamber in sequence.

[0026] Optionally, when the reaction gas source includes an indium source, a phosphorus source and an arsenic source, in step S2, the step of providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device for a thin film growth reaction includes controlling the introduction of a phosphorus source and an indium source into the reaction chamber, and then introducing an indium source, an aluminum source and an arsenic source.

[0027] Optionally, the aluminum source includes an aluminum-containing metal organic compound, the gallium source includes a gallium-containing metal organic compound, the arsenic source includes an arsenic-containing hydride, the phosphorus source includes a phosphorus-containing hydride, and the indium source includes an indium-containing metal organic compound.

[0028] Optionally, the gas injection device is opposite to the middle portion of the rotating base, and the wafer carrier area surrounds the middle portion of the rotating base, so that the gas injection device provides laminar gas flowing through the wafer carrier area.

[0029] The present invention also provides a method for preparing a III-V group compound film, comprising the following steps:

[0030] S11: obtaining a pretreatment reaction chamber obtained by the pretreatment method, and removing the companion wafer in the pretreatment reaction chamber;

[0031] S12: placing the substrate into the wafer carrier area of ​​the pretreatment reaction chamber, controlling the top plate temperature of the temperature-controllable top plate to be 15-25° C. higher than the top plate temperature controlled in the pretreatment method, the base temperature of the rotating base to be 600-720° C., the chamber pressure of the pretreatment reaction chamber to be 35-100 mbar, and the rotation speed of the rotating base to be 6-15 rpm;

[0032] S13: providing an aluminum source and a reaction gas source into the pretreatment reaction chamber through the gas injection device to form a III-V compound thin film on the substrate;

[0033] The reaction gas source includes at least two of an indium source, an aluminum source, a gallium source, an arsenic source, and a phosphorus source.

[0034] The beneficial effects of the method for preparing a III-V compound film are as follows: a III-V compound film is prepared by using a pretreatment reaction chamber obtained by the pretreatment method, and the pretreatment reaction chamber provides a good process environment for film preparation; the top plate temperature of the temperature-controllable top plate is controlled to be 15-25°C higher than the top plate temperature controlled in the pretreatment method, and the base temperature of the rotating base is 600-720°C, which is conducive to forming a reasonable temperature gradient field in the reaction space, reducing or avoiding the reaction gas consumption caused by the pre-reaction of the reaction gas source near the temperature-controllable top plate, the deposition of top plate particles, and the aggregation of top plate droplets; combined with controlling the chamber pressure of the pretreatment reaction chamber to be 35-100 mbar and the rotation rate of the rotating base to be 6-15 rpm, it is conducive to forming a good quality III-V compound film on the substrate.

[0035] Optionally, in step S13, flow control of at least two of the following sources is performed: the flow of the aluminum source is 60~180sccm, the flow of the gallium source is 15~45sccm, the flow of the arsenic source is 60~450sccm, the flow of the indium source is 400-1200sccm, and the flow of the phosphorus source is 600-1200sccm.

[0036] Optionally, the reaction gas source is a pre-reaction gas source in the pre-treatment method, or is an aluminum source and a pre-reaction gas source in the pre-treatment method.

[0037] Optionally, in step S13, the flow rate control of the reaction gas source is consistent with the flow rate control of the pre-reaction gas source in the pretreatment method, or is consistent with the flow rate control of the aluminum source and the pre-reaction gas source in the pretreatment method.

[0038] Optionally, the substrate is a GaAs substrate or an InP substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic diagram of the structure of a vapor phase growth device according to an embodiment of the present invention;

[0040] Figure 2 is a flow chart of a method for preparing a Group III-V compound thin film in an embodiment of the present invention;

[0041] Figure 3 This is a microscopic electron microscope photograph of a GaAs-based semiconductor film according to an embodiment of the present invention, with a magnification of 100 times;

[0042] Figure 4 A photograph of a portion of the bottom plate of the chamber cover of the vapor phase growth device according to an embodiment of the present invention;

[0043] Figure 5 This is a microscopic electron microscope photograph of the InP-based semiconductor film of an embodiment of the present invention, with a magnification of 100 times;

[0044] Figure 6 This is a photograph of a partial area of ​​the bottom plate of the chamber cover of the vapor phase growth equipment of the comparative example of the present invention. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0046] An embodiment of the present invention provides a vapor phase growth device, specifically a MOCVD reaction device.

[0047] Reference Figure 1 The MOCVD equipment shown includes a reaction chamber 100, a temperature-controllable top plate 101 disposed on the top of the reaction chamber 100, a temperature-controllable rotating base 102 disposed in the reaction chamber 100, and a gas injection device 103 disposed on the temperature-controllable top plate 101 and corresponding to the rotating base 102. The top surface of the rotating base 102 includes a wafer carrier area 104.

[0048] A top heating device (such as a heating plate) is arranged inside the temperature-controllable top plate 101, and the heating control of the top heating device is arranged outside the reaction chamber 100 to realize the heating control of the temperature-controllable top plate 101. The specific implementation method is a conventional technical means in the art.

[0049] The gas injection device 103 is disposed opposite to the middle of the rotating base 102, and the wafer carrier area 104 surrounds the middle of the rotating base 102. The gas injection device 103 is configured to deliver process gas (e.g., gas for reaction, gas for purging, etc.) to the rotating base 102 and allow the gas to flow through the wafer carrier area in a laminar flow manner. The specific implementation of the gas injection device 103 is a conventional technical means in the art.

[0050] The susceptor heating device 105 is disposed under the temperature-controllable rotating susceptor 102 to provide heat for the rotating susceptor 102. The rotating susceptor 102 transfers heat to the companion sheet or substrate placed in the wafer carrier area so that the temperature of the companion sheet or substrate is consistent with the temperature of the rotating susceptor 102. In some specific embodiments, the susceptor heating device 105 is a resistive heater. The heating control of the susceptor heating device 105 is disposed outside the reaction chamber 100, and the specific implementation method is a conventional technical means of those skilled in the art.

[0051] The rotating base 102 is driven to rotate by the rotating device 106 to facilitate uniform mixing of the process gas above the substrate and facilitate uniform film formation. In some specific embodiments, the rotating device 106 is a magnetic fluid rotating seal assembly, which is specifically implemented by conventional technical means in the art.

[0052] The MOCVD equipment is also provided with a vacuum system connected to the reaction chamber 100 to adjust the pressure of the reaction chamber 100 according to the process requirements. In addition, an exhaust device is also provided at the bottom of the reaction chamber 100 to exhaust the tail gas during the process to ensure the pressure in the reaction chamber 100.

[0053] In some embodiments, the ratio of the diameter of the rotating base 102 to the height of the reaction space in the reaction chamber 100 is 12:1 to 40:1. The height of the reaction space is the height between the bottom surface of the temperature-controllable top plate 101 and the top surface of the rotating base 102. The space surrounded by the bottom surface of the temperature-controllable top plate 101, the top surface of the rotating base 102 and the inner wall of the reaction chamber 100 is the reaction space.

[0054] In some embodiments, the height of the reaction space is 15-50 mm.

[0055] In some embodiments, the diameter of the rotating base 102 is 600 mm. In some embodiments, the diameter of the rotating base 102 is 800 mm.

[0056] In the process from when the process gas enters the gas injection device 103 to when it is heated in the reaction chamber 100 after being ejected and flows toward the substrate carried by the wafer carrier area 104, the reaction chamber 100 should be controlled to have a reasonable temperature gradient field in the axial direction, that is, the temperature of the temperature-controllable top plate 101 and the temperature of the rotating base 102 should be reasonably controlled. In particular, if the temperature of the temperature-controllable top plate 101 is too low, the process gas will not easily reach the process temperature required for the film growth reaction when it reaches the upper part of the substrate, thereby affecting the film growth quality, and it is easy to condense on the temperature-controllable top plate to form droplets due to the diffusion of the gas; if the temperature is too high, the process gas will easily be heated to an excessively high temperature before reaching the upper part of the substrate, and it is easy to pre-react on the temperature-controllable top plate 101 due to the diffusion of the gas, resulting in the consumption of the process gas, and particles will easily be deposited on the temperature-controllable top plate 101 due to the pre-reaction, and these particles will affect the film quality once they fall.

[0057] For the vapor phase growth process of Group III-V compound thin films, if the reaction chamber 100 is first used to deposit other semiconductor thin films of different composition materials, the deposition layer formed on the chamber wall and the base may be detrimental to the growth process.

[0058] In some embodiments, the Group III-V compound film is a GaAs-based semiconductor film or an InP-based semiconductor film.

[0059] An embodiment of the present invention provides a pretreatment method for a vapor phase growth device, wherein the pretreatment method uses Figure 1 The vapor phase growth device shown in the figure, after placing the companion film in the wafer carrier area of ​​the vapor phase growth device, refer to Figure 2 , perform the following steps:

[0060] S1: Controlling the top plate temperature of the temperature-controllable top plate to 130-170° C., the base temperature of the rotating base to 600-720° C., the chamber pressure in the reaction chamber to 35-100 mbar, and the rotation speed of the rotating base to 6-15 rpm;

[0061] S2: Providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device to perform a thin film growth reaction until an aluminum-containing Group III-V compound thin film of a preset thickness is formed on the exposed surfaces of the inner wall of the reaction chamber and the top surface of the rotating base.

[0062] In some embodiments, the pre-reaction gas source includes at least two of a gallium source, an arsenic source, an indium source, and a phosphorus source.

[0063] In some embodiments, the aluminum source includes an aluminum-containing metal organic compound, the gallium source includes a gallium-containing metal organic compound, the arsenic source includes an arsenic-containing hydride, the phosphorus source includes a phosphorus-containing hydride, and the indium source includes an indium-containing metal organic compound.

[0064] In some embodiments, the aluminum source comprises an aluminum alkyl compound, such as trimethylaluminum TMAl.

[0065] In some embodiments, the gallium source includes a gallium alkyl compound, such as trimethylgallium (TMGa).

[0066] In some embodiments, the indium source includes an indium alkyl compound, such as trimethylindium TMIn.

[0067] In some embodiments, the arsenic source comprises arsine AsH 3 .

[0068] In some embodiments, the phosphorus source comprises phosphine (PH3).

[0069] In some embodiments, the pre-reaction gas source includes a gallium source and an arsenic source.

[0070] In some embodiments, the pre-reaction gas source includes an indium source, a phosphorus source, and an arsenic source.

[0071] In some embodiments, in step S1, the top plate temperature is controlled to be 130-140°C.

[0072] In some embodiments, in step S2, the preset thickness of the aluminum-containing III-V compound film is 2-8 μm. If the preset thickness of the aluminum-containing III-V compound film is less than 2 μm, it is easy for the top surface of the rotating base and / or the side wall of the reaction chamber to have areas not covered by the aluminum-containing III-V compound film. If the preset thickness of the aluminum-containing III-V compound film is greater than 8 μm, in the subsequent process of preparing the III-V compound film, the overly thick pre-deposited aluminum-containing III-V compound film is easily peeled off due to the effect of the process environment gas flow field, thereby affecting the quality of the III-V compound film.

[0073] In some embodiments, in step S2, the flow rate of the aluminum source is controlled to be 60-180 sccm.

[0074] In step S2 of some embodiments, flow rates of at least two of the following sources are controlled: the flow rate of the gallium source is 15-45 sccm, the flow rate of the arsenic source is 60-450 sccm, the flow rate of the indium source is 400-1200 sccm, and the flow rate of the phosphorus source is 600-1200 sccm.

[0075] In some embodiments, each of the pre-reaction gas sources is carried into the reaction chamber by a carrier gas. In some specific embodiments, the carrier gas is hydrogen.

[0076] In some embodiments, when the pre-reaction gas source includes a gallium source and an arsenic source, in step S2, the step of providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device for a thin film growth reaction includes: controlling the flow rate of the gallium source to 15~45sccm, and the flow rate of the arsenic source to 150~450sccm.

[0077] In some embodiments, when the pre-reaction gas source includes a gallium source and an arsenic source, the V / III ratio of the mixed gas composed of the arsenic source and the gallium source is controlled to be 30-150.

[0078] In some embodiments, when the pre-reaction gas source includes an indium source, a phosphorus source and an arsenic source, in step S2, the step of providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device for a thin film growth reaction includes: controlling the flow rate of the indium source to 400-1200sccm, the flow rate of the phosphorus source to 600-1200sccm, and the flow rate of the arsenic source to 60~180sccm.

[0079] In some embodiments, when the pre-reaction gas source includes an indium source, a phosphorus source and an arsenic source, it also includes controlling the V / III ratio of the mixed gas composed of the indium source, the phosphorus source and the arsenic source to be 60-200.

[0080] The V / III ratio is defined as the ratio between the molar amount of the reaction gas containing the Group V element and the molar amount of the reaction gas containing the Group III element in the pre-reaction gas source. For example, when the pre-reaction gas source includes a gallium source and an arsenic source, the V / III ratio is the ratio between the molar amount of the arsenic source reaction gas and the molar amount of the gallium source reaction gas. When the pre-reaction gas source includes an indium source and a phosphorus source, the V / III ratio is the ratio between the molar amount of the phosphorus source reaction gas and the molar amount of the indium source reaction gas.

[0081] In some embodiments, before executing step S1, the step further includes performing a water and oxygen removal treatment on the reaction chamber, including the following steps:

[0082] Sa1: providing a purge gas into the reaction chamber through the gas injection device, controlling the base temperature of the rotating base to rise to a first temperature, and controlling the chamber pressure in the reaction chamber to be the same as the chamber pressure in the reaction chamber in step S1;

[0083] Sa2: providing an arsenic source or a phosphorus source into the reaction chamber through the gas injection device, and controlling the temperature of the susceptor to rise to a temperature higher than the susceptor temperature in step S1 and then continue for a preset time.

[0084] In some embodiments, in step Sa2, the base temperature is controlled to be 10-30°C higher than the base temperature in step S1, the preset time is 3-10 minutes, and the first temperature is 180-320°C.

[0085] The main function of step Sa1 is to remove water, and the main function of step Sa2 is to remove oxygen and further remove any water that may still exist. Since the reaction chamber contains water and oxygen, if the water and oxygen content is too high, the water and oxygen will excessively consume the reaction gas source. Through the water and oxygen removal treatment, water and oxygen can be maintained within a reasonable range (as low as possible), reducing the consumption of the reaction gas source and ensuring the normal progress of subsequent processes. In step Sa2, if the base temperature is too low, the water and oxygen removal efficiency will be too low. If the base temperature is too high, since the rotating base needs to be cooled later, the processing efficiency will be dragged down due to the high base temperature. The base temperature in step Sa2 is set to be 10~30℃ higher than the base temperature in step S1, taking into account both the water and oxygen removal efficiency and the cooling efficiency.

[0086] The duration of steps Sa1 and Sa2, the selection of the first temperature and the base temperature in step Sa2, and the control of the heating rate of each step are adaptively adjusted according to the water-oxygen content in the reaction chamber and the process requirements. If the water-oxygen content in the reaction chamber is low, the water-removal oxygen treatment can be carried out at a relatively low temperature for a longer time, for example, in step Sa1, the water-removal oxygen treatment is carried out at 150 degrees Celsius for 20 minutes. It is also possible to carry out the water-removal oxygen treatment for a shorter time at a relatively high temperature, for example, in step Sa1, the water-removal oxygen treatment is carried out at 300 degrees Celsius for 10 minutes. If the water-oxygen content in the reaction chamber is high, carrying out the water-removal oxygen treatment for a longer time at a relatively low temperature will result in high energy consumption, and it is preferred to carry out the water-removal oxygen treatment for a shorter time at a relatively high temperature.

[0087] In some embodiments, the purge gas used in step Sa1 is hydrogen.

[0088] The embodiment of the present invention further provides a method for preparing a III-V compound thin film using the pretreatment chamber obtained through the above steps S1 and S2, comprising:

[0089] S11: after obtaining the pretreatment reaction chamber, removing the companion wafer in the pretreatment reaction chamber;

[0090] S12: placing the substrate into the wafer carrier area of ​​the pretreatment reaction chamber, controlling the top plate temperature of the temperature-controllable top plate to be 15-25° C. higher than the top plate temperature controlled in the pretreatment method, the base temperature of the rotating base to be 600-720° C., the chamber pressure of the pretreatment reaction chamber to be 35-100 mbar, and the rotation speed of the rotating base to be 6-15 rpm;

[0091] S13: providing a reaction gas source into the pre-treatment reaction chamber through the gas injection device to form a Group III-V compound thin film on the substrate.

[0092] In some embodiments, the substrate is a GaAs substrate or an InP substrate.

[0093] In step S12, the top plate temperature of the temperature-controllable top plate is controlled to be 15-25°C higher than the top plate temperature controlled in the pretreatment method, which is conducive to forming a reasonable temperature gradient field in the reaction space, reducing or avoiding the reaction gas consumption caused by the pre-reaction of the reaction gas source near the temperature-controllable top plate, the deposition of particles on the top plate, and the aggregation of droplets on the top plate.

[0094] In step S12 of some embodiments, the base temperature of the rotating base is controlled to be equivalent to the base temperature controlled in step S1 of the aforementioned pretreatment method.

[0095] In step S12 of some embodiments, the chamber pressure of the pretreatment reaction chamber is controlled to be equivalent to the chamber pressure controlled in step S1 of the aforementioned pretreatment method.

[0096] In step S12 of some embodiments, the rotation rate of the rotating base is equivalent to the rotation rate controlled in step S1 of the aforementioned preprocessing method.

[0097] In some embodiments, the reaction gas source includes at least two of an indium source, an aluminum source, a gallium source, an arsenic source, and a phosphorus source.

[0098] In step S13 of some embodiments, flow control of at least two of the following sources is performed: the flow of the aluminum source is 60~180sccm, the flow of the gallium source is 15~45sccm, the flow of the arsenic source is 60~450sccm, the flow of the indium source is 400-1200sccm, and the flow of the phosphorus source is 600-1200sccm.

[0099] In some embodiments, the reaction gas source is a pre-reaction gas source in the pretreatment method.

[0100] In some embodiments, the reaction gas source is the aluminum source and the pre-reaction gas source in the pretreatment method.

[0101] In some embodiments, in step S13, the flow rate control of the reaction gas source is consistent with the flow rate control of the pre-reaction gas source in the pretreatment method.

[0102] In some embodiments, in step S13, the flow rate control of the reaction gas source is consistent with the flow rate control of the aluminum source and the pre-reaction gas source in the pretreatment method.

[0103] In some embodiments, step S12 further includes: after placing the substrate in the wafer carrier area of ​​the pretreatment reaction chamber, performing a dehydration and oxygen removal treatment on the pretreatment reaction chamber. The process of performing a dehydration and oxygen removal treatment on the pretreatment reaction chamber in step S12 can refer to the process of performing a dehydration and oxygen removal treatment on the reaction chamber before step S1 in the aforementioned pretreatment method.

[0104] Embodiment 1

[0105] This embodiment provides a Figure 1 The pretreatment method of the MOCVD device shown, and the method for preparing GaAs-based semiconductor film using the pretreatment device obtained by the pretreatment method, the base diameter of the rotating base of the MOCVD device is 600mm, and the height of the reaction space in the reaction chamber is 25mm.

[0106] A companion wafer is placed in the wafer carrier area, and hydrogen is provided as a purge gas into the reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 280°C, and the chamber pressure in the reaction chamber is controlled to be 60 mbar. Then, an arsenic source is provided into the reaction chamber through the gas injection device, and the base temperature of the rotating base is controlled to rise to 695°C and maintained for 7 minutes to complete the dehydration and oxygen treatment of the reaction chamber.

[0107] The preprocessing method is as follows:

[0108] In step S1, the top plate temperature of the temperature-controllable top plate is controlled to be 135° C., the base temperature of the rotating base is controlled to be 680° C., the chamber pressure in the reaction chamber is controlled to be 60 mbar, and the rotation speed of the rotating base is controlled to be 10 rpm;

[0109] In step S2, an arsenic source is continuously introduced into the reaction chamber at a flow rate of 150 sccm through the gas injection device, and then a gallium source is introduced at a flow rate of 45 sccm and an aluminum source is introduced at a flow rate of 80 sccm in sequence, and the V / III ratio in the mixed gas composed of the arsenic source and the gallium source is controlled to be 30-150, until a pre-coated film with a thickness of 2 μm and composed of alternately stacked GaAs films and AlAs films is formed on the inner wall of the reaction chamber, the exposed surface of the top surface of the rotating base, and the surface of the companion film.

[0110] After step S2 is completed, the gallium source and the aluminum source are stopped from being introduced into the reaction chamber through the gas injection device, and the temperature-controllable top plate and the rotating base are controlled to start cooling down. When the base temperature of the rotating base is less than 280° C., the arsenic source is stopped from being introduced into the reaction chamber through the gas injection device, and the rotating base is controlled to stop rotating. When the temperature-controllable top plate and the rotating base are controlled to cool down to room temperature, a pretreatment reaction chamber is obtained.

[0111] The preparation method of GaAs-based semiconductor thin film is as follows:

[0112] In step S11, the companion wafer in the pretreatment reaction chamber is removed, and the GaAs substrate is placed in the wafer carrier area of ​​the pretreatment reaction chamber;

[0113] Hydrogen is provided as a purge gas to the pretreatment reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 280°C and the chamber pressure in the pretreatment reaction chamber is controlled to be 60 mbar, and then an arsenic source is provided to the pretreatment reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 695°C and maintained for 7 minutes to complete the dehydration and oxygen treatment of the pretreatment reaction chamber.

[0114] In step S12, the top plate temperature of the temperature-controllable top plate is controlled to be 155° C., the base temperature of the rotating base is controlled to be 680° C., the chamber pressure in the pretreatment reaction chamber is controlled to be 60 mbar, and the rotation speed of the rotating base is controlled to be 10 rpm.

[0115] In step S13, an arsenic source is continuously introduced into the reaction chamber at a flow rate of 150 sccm through the gas injection device, and a gallium source is alternately introduced at a flow rate of 45 sccm and an aluminum source is alternately introduced at a flow rate of 80 sccm, and the V / III ratio in the mixed gas composed of the arsenic source and the gallium source is controlled to be 30-150, until alternatingly stacked GaAs films and AlAs films are formed on the GaAs substrate.

[0116] After step S13 is completed, the gallium source and the aluminum source are stopped from being introduced into the pretreatment reaction chamber through the gas injection device, and the temperature-controllable top plate and the rotating base are controlled to start cooling down. When the base temperature of the rotating base is less than 280°C, the arsenic source is stopped from being introduced into the pretreatment reaction chamber through the gas injection device, and the rotating base is controlled to stop rotating. When the temperature-controllable top plate and the rotating base are controlled to cool down to room temperature.

[0117] Embodiment 2

[0118] This embodiment provides a Figure 1 The pretreatment method of the MOCVD device shown, and the method for preparing InP-based semiconductor film using the pretreatment device obtained by the pretreatment method, the base diameter of the rotating base in the MOCVD device is 800mm, and the height of the reaction space in the reaction chamber is 45mm.

[0119] A companion wafer is placed in the wafer carrier area, and hydrogen is provided as a purge gas into the reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 180°C and the chamber pressure in the reaction chamber is controlled to be 70 mbar, and then a phosphorus source is provided into the reaction chamber through the gas injection device, and the base temperature of the rotating base is controlled to rise to 655°C and maintained for 8 minutes to complete the dehydration and oxygen treatment of the reaction chamber.

[0120] The preprocessing method is as follows:

[0121] In step S1, the top plate temperature of the temperature-controllable top plate is controlled to be 130° C., the base temperature of the rotating base is controlled to be 640° C., the chamber pressure in the reaction chamber is controlled to be 70 mbar, and the rotation speed of the rotating base is controlled to be 15 rpm.

[0122] In step S2, after the indium source and phosphorus source are introduced into the reaction chamber through the gas injection device, the indium source, aluminum source and arsenic source are introduced, and this is repeated alternately until a pre-coated film with a thickness of 5 μm formed by alternating InP film and InAlAs film is formed on the inner wall of the reaction chamber, the exposed surface of the top surface of the rotating base and the surface of the companion film. The indium source flow rate is controlled to be 800 sccm, the phosphorus source flow rate is 1000 sccm, the aluminum source flow rate is 150 sccm, and the arsenic source flow rate is 90 sccm, and the V / III ratio of the mixed gas composed of the indium source, phosphorus source and arsenic source is 60-200.

[0123] After step S2 is completed, the gas injection device stops introducing the indium source, aluminum source and arsenic source into the reaction chamber, and controls the temperature-controllable top plate and the rotating base to start cooling down. When the base temperature of the rotating base is less than 180° C., the gas injection device stops introducing the phosphorus source into the reaction chamber, and controls the rotating base to stop rotating. When the temperature-controllable top plate and the rotating base are both cooled to room temperature, a pretreatment reaction chamber is obtained.

[0124] The preparation method of InP-based semiconductor film is as follows:

[0125] In step S11, the companion wafer in the pretreatment reaction chamber is removed, and the InP substrate is placed in the wafer carrier area of ​​the pretreatment reaction chamber;

[0126] Hydrogen is provided as a purge gas to the pretreatment reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 180°C and the chamber pressure in the pretreatment reaction chamber is controlled to be 70 mbar, and then a phosphorus source is provided to the pretreatment reaction chamber through the gas injection device, the base temperature of the rotating base is controlled to rise to 655°C and maintained for 8 minutes to complete the dehydration and oxygen treatment of the pretreatment reaction chamber.

[0127] In step S12, the top plate temperature of the temperature-controllable top plate is controlled to be 150° C., the base temperature of the rotating base is controlled to be 640° C., the chamber pressure in the pretreatment reaction chamber is controlled to be 70 mbar, and the rotation speed of the rotating base is controlled to be 15 rpm.

[0128] In step S13, after the indium source and the phosphorus source are introduced into the reaction chamber by the gas injection device, the indium source, the aluminum source and the arsenic source are introduced into the reaction chamber by the gas injection device, and the process is repeated alternately. The indium source flow rate is controlled to be 800sccm, the phosphorus source flow rate is 1000sccm, the aluminum source flow rate is 150sccm, and the arsenic source flow rate is 90sccm. The V / III ratio of the mixed gas composed of the indium source, the phosphorus source and the arsenic source is 60-200, until an InP film and an InAlAs film having a thickness required by the process and alternating in sequence are formed on the InP substrate.

[0129] After step S13 is completed, the gas injection device stops introducing the indium source, aluminum source and arsenic source into the pretreatment reaction chamber, and controls the temperature-controllable top plate and the rotating base to start cooling down. When the base temperature of the rotating base is less than 180°C, the gas injection device stops introducing the phosphorus source into the pretreatment reaction chamber, and controls the rotating base to stop rotating. When the temperature-controllable top plate and the rotating base are both controlled to cool down to room temperature, the preparation of the InP-based semiconductor film is completed.

[0130] After S13 of the first embodiment is completed, the obtained GaAs-based semiconductor film is as follows: Figure 3 As shown in the electron microscope photo of the pretreatment equipment, there is no particle contamination on the surface. Figure 4 It is shown that there is no particle deposition and droplet aggregation.

[0131] After S13 of the second embodiment is completed, the obtained InP-based semiconductor film is as follows: Figure 5 The electron microscope photo shows that there is no particle contamination on the surface. There is no particle deposition and droplet aggregation on the temperature-controlled top plate of the pretreatment equipment.

[0132] The present application provides a comparative example, which is different from the first embodiment in that the temperature of the temperature-controllable top plate is controlled to be 180° C. in step S12. After the execution of step S13 of the comparative example is completed, refer to Figure 6 , there is a phenomenon of particle deposition on its temperature-controlled top plate.

[0133] Although the embodiments of the present invention are described in detail above, it is obvious to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations are within the scope and spirit of the present invention as described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in a variety of ways.

Claims

1. A pretreatment method for a vapor phase growth device, characterized in that: The following steps are involved: S0: Provide a vapor phase growth device, the vapor phase growth device comprising a reaction chamber, a temperature-controllable top plate disposed on the top of the reaction chamber, a temperature-controllable rotating base disposed in the reaction chamber, and a gas injection device disposed on the temperature-controllable top plate and opposite to the rotating base, the top surface of the rotating base comprising a wafer carrier area, a companion wafer is placed in the wafer carrier area, and the ratio of the diameter of the rotating base to the height of the reaction space in the reaction chamber is 12:1 to 40:1; S1: Controlling the top plate temperature of the temperature-controllable top plate to 130-170° C., the base temperature of the rotating base to 600-720° C., the chamber pressure in the reaction chamber to 35-100 mbar, and the rotation speed of the rotating base to 6-15 rpm; S2: Providing an aluminum source and a pre-reaction gas source into the reaction chamber through the gas injection device to perform a thin film growth reaction until an aluminum-containing III-V compound thin film of a preset thickness is formed on the exposed surface of the inner wall of the reaction chamber and the top of the rotating base; The pre-reaction gas source includes at least two of a gallium source, an arsenic source, an indium source and a phosphorus source; In step S2, the preset thickness of the aluminum III-V compound film is 2-8 μm.

2. The pretreatment method according to claim 1, characterized in that Before executing step S1, the process further includes performing a water and oxygen removal treatment on the reaction chamber, including the following steps: Sa1: providing a purge gas into the reaction chamber through the gas injection device, controlling the base temperature of the rotating base to rise to 180-320 degrees Celsius, and controlling the chamber pressure in the reaction chamber to be the same as the chamber pressure in the reaction chamber in step S1; Sa2: providing an arsenic source or a phosphorus source into the reaction chamber through the gas injection device, controlling the temperature of the susceptor to rise to a temperature higher than the susceptor temperature in step S1, and then continuing for a preset time.

3. The pretreatment method according to claim 2, characterized in that: In step Sa2, the base temperature is controlled to be 10-30° C. higher than the base temperature in step S1, and the preset time is 3-10 minutes.

4. The pretreatment method according to claim 1, characterized in that: The height of the reaction space is 15-50 mm, and the height of the reaction space is the height between the bottom surface of the temperature-controllable top plate and the top surface of the rotating base.

5. The pretreatment method according to claim 1, characterized in that: In step S2, the flow rate of the aluminum source is controlled to be 60-180 sccm, and the flow rates of at least two of the following sources are controlled: The flow rate of the gallium source is 15~45sccm, the flow rate of the arsenic source is 60~450sccm, the flow rate of the indium source is 400-1200sccm, and the flow rate of the phosphorus source is 600-1200sccm.

6. The pretreatment method according to claim 5, characterized in that: When the pre-reaction gas source includes a gallium source and an arsenic source, the flow rate of the gallium source is controlled to be 15-45 sccm, and the flow rate of the arsenic source is controlled to be 150-450 sccm.

7. The pretreatment method according to claim 6, characterized in that: The method also includes controlling the V / III ratio of the mixed gas composed of an arsenic source and a gallium source to be 30-150.

8. The pretreatment method according to claim 5, characterized in that: When the pre-reaction gas source includes an indium source, a phosphorus source and an arsenic source, the flow rate of the indium source is controlled to be 400-1200 sccm, the flow rate of the phosphorus source is controlled to be 600-1200 sccm, and the flow rate of the arsenic source is controlled to be 60-180 sccm.

9. The pretreatment method according to claim 8, characterized in that: The method also includes controlling the V / III ratio of the mixed gas composed of an indium source, a phosphorus source and an arsenic source to be 60-200.

10. The pretreatment method according to claim 1, characterized in that: In step S2, the step of providing an aluminum source and a pre-reaction gas source into the reaction chamber by the gas injection device to perform a thin film growth reaction includes: When the pre-reaction gas source includes a gallium source and an arsenic source, the arsenic source is controlled to be continuously introduced into the reaction chamber, and the gallium source and the aluminum source are alternately introduced into the reaction chamber in sequence; When the reaction gas source includes an indium source, a phosphorus source and an arsenic source, the phosphorus source and the indium source are controlled to be introduced into the reaction chamber, and then the indium source, the aluminum source and the arsenic source are introduced.

11. The pretreatment method according to claim 1, characterized in that: The aluminum source includes an aluminum-containing metal organic compound, the gallium source includes a gallium-containing metal organic compound, the arsenic source includes an arsenic-containing hydride, the phosphorus source includes a phosphorus-containing hydride, and the indium source includes an indium-containing metal organic compound.

12. A method for preparing a III-V compound film, characterized in that: The following steps are involved: S11: obtaining a pretreatment reaction chamber obtained by the pretreatment method according to any one of claims 1 to 11, and removing the companion wafer in the pretreatment reaction chamber; S12: placing the substrate into the wafer carrier area of ​​the pretreatment reaction chamber, controlling the top plate temperature of the temperature-controllable top plate to be 15-25° C. higher than the top plate temperature controlled in the pretreatment method, the base temperature of the rotating base to be 600-720° C., the chamber pressure of the pretreatment reaction chamber to be 35-100 mbar, and the rotation speed of the rotating base to be 6-15 rpm; S13: providing a reaction gas source into the pretreatment reaction chamber through the gas injection device to form a III-V compound thin film on the substrate; The reaction gas source includes at least two of an indium source, an aluminum source, a gallium source, an arsenic source, and a phosphorus source.

13. The method for preparing a Group III-V compound thin film according to claim 12, characterized in that: In step S13, flow control of at least two sources is performed as follows: The flow rate of the aluminum source is 60~180sccm, the flow rate of the gallium source is 15~45sccm, the flow rate of the arsenic source is 60~450sccm, the flow rate of the indium source is 400-1200sccm, and the flow rate of the phosphorus source is 600-1200sccm.

14. The method for preparing a Group III-V compound thin film according to claim 12, characterized in that: The reaction gas source is the pre-reaction gas source in the pre-treatment method, or is the aluminum source and the pre-reaction gas source in the pre-treatment method.

15. The method for preparing a Group III-V compound thin film according to claim 14, characterized in that: In step S13, the flow rate control of the reaction gas source is consistent with the flow rate control of the pre-reaction gas source in the pretreatment method, or is consistent with the flow rate control of the aluminum source and the pre-reaction gas source in the pretreatment method.

16. The method for preparing a Group III-V compound thin film according to claim 12, characterized in that: The substrate is a GaAs substrate or an InP substrate.

Images