Automatic growth raw material adding device, automatic growth raw material adding method and application

Abstract

The invention discloses an automatic growth raw material adding device, an automatic growth raw material adding method and application. The automatic growth raw material adding device comprises a conveying channel, a first air chamber, a second air chamber and a third air chamber, the first gas chamber is used for accommodating first growth source gas; the second gas chamber is in heat conduction connection with the first gas chamber and is used for accommodating second growth source gas; the third gas chamber is adjacent to the first gas chamber, is communicated with the growth raw material storage chamber and is used for accommodating third gas; when the temperature of the second growth source gas is higher than that of the first growth source gas, the first gas chamber enters an expansion state and extrudes the third gas chamber, so that at least part of third gas in the third gas chamber enters the growth raw material storage chamber and applies pressure to the growth raw material in the growth raw material storage chamber; and then at least part of the growth raw materials are driven to be transferred into the at least two reaction chambers along the conveying channel. The growth raw materials can be automatically added in two different growth modes at the same time, and the method can be applied to the field of growth of gallium nitride or aluminum nitride substrates.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor materials, and in particular to an automatic growth material adding device, a method for automatically adding growth materials, and applications thereof. Background Art

[0002] GaN is an important wide bandgap semiconductor material, which is widely used in the preparation of high-brightness light-emitting diodes (LEDs), semiconductor lasers and high-power electronic devices. The traditional method uses the hydride vapor phase epitaxy (HVPE) method to grow GaN at a high speed to prepare single-crystal gallium nitride single crystal substrates; however, it is very difficult to prepare high-quality gallium nitride single crystal substrates due to the difficulty in controlling the process conditions.

[0003] In order to obtain higher quality GaN, the reaction mode of Cl2 and metal gallium is introduced into the traditional HVPE gallium boat design, that is, two growth modes are adopted. The hydride vapor phase epitaxy (HVPE) method grows GaN on the gallium surface of the gallium nitride substrate, and the trihalide vapor phase epitaxy (THVPE) method grows GaN on the nitrogen surface. The THVPE growth mode requires a higher temperature, which can achieve the growth of GaN on the N polar surface, so that the polarization effect will be improved, the N polarity can grow a plane, and the Ga surface grows a hexagonal pyramid. The product can work at a higher frequency and improve the quality. However, in the two growth modes, during the chemical reaction between HCl / Cl2 and gallium liquid to generate gaseous GaCl / GaCl3, due to the continuous consumption of chemical reactions, the gallium liquid cannot be replenished in time, and GaCl / GaCl3 cannot be continuously generated. Artificial addition of gallium liquid will cause large fluctuations in temperature drop, which will cause changes in the GaN interface layer when the GaN crystal grows after cooling, and then continue to grow, which will affect the product quality. Therefore, a new method is needed to add gallium liquid in time in the two growth modes, so as to achieve efficient and continuous growth of GaN crystals. Summary of the invention

[0004] The main purpose of the present invention is to provide an automatic growth material adding device, an automatic growth material adding method and application, so as to overcome the deficiencies in the prior art.

[0005] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes:

[0006] A first aspect of the present invention provides a device for automatically adding growth materials, comprising:

[0007] Conveying channel;

[0008] A first gas chamber, which is used to accommodate a first growth source gas;

[0009] a second gas chamber, thermally connected to the first gas chamber and used for accommodating a second growth source gas;

[0010] a third gas chamber, which is disposed adjacent to the first gas chamber and communicated with the growth material storage chamber and is used to contain a third gas;

[0011] Among them, when the temperature of the second growth source gas in the second gas chamber is higher than the temperature of the first growth source gas in the first gas chamber, the first gas chamber enters an expansion state and squeezes the third gas chamber, so that at least part of the third gas in the third gas chamber enters the growth raw material storage chamber and applies pressure to the growth raw material therein, thereby driving at least part of the growth raw material therein to transfer along the transport channel into at least two reaction chambers.

[0012] In some embodiments, the first air chamber and the third air chamber are sealed and isolated from each other via a movable baffle or an elastic membrane.

[0013] In some embodiments, the third air chamber is disposed between the first air chamber and the second air chamber, or the second air chamber is disposed adjacent to the first air chamber.

[0014] In some preferred embodiments, the adjacent second air chamber and the first air chamber are sealed and isolated from each other via a heat-conducting baffle.

[0015] In some embodiments, the first growth source gas includes GaCl and the second growth source gas includes GaCl3.

[0016] In some embodiments, in order to minimize the thermal expansion of the third gas, the third gas is an inert gas having a thermal expansion coefficient of less than 0.001 / °C.

[0017] In some embodiments, the temperature of the first growth source gas is 800-900°C.

[0018] In some embodiments, the temperature of the second growth source gas is 1200-1400°C.

[0019] In some embodiments, the growth material includes gallium liquid or aluminum liquid; when the growth material is aluminum liquid, the semiconductor film layer can be AlN crystal.

[0020] A second aspect of the present invention provides a method for automatically adding growth materials, the method being implemented based on the aforementioned automatic growth material adding device, the method comprising:

[0021] A first growth source gas and a second growth source gas are input into the first air chamber and the second air chamber respectively; wherein the temperature of the second growth source gas is higher than that of the first growth source gas, and the second air chamber is thermally connected to the first air chamber, so that the first air chamber enters an expanded state and squeezes a third air chamber adjacent to the first air chamber, so as to drive at least part of the third gas in the third air chamber to enter the growth material storage chamber and apply pressure to the growth material therein, thereby driving at least part of the growth material therein to transfer along the transport channel into at least two reaction chambers.

[0022] In some embodiments, the method of automatically adding growth materials further comprises the following steps:

[0023] S11: introducing a first reaction gas into the first reaction chamber, allowing the growth material to react with the first reaction gas in the first reaction chamber to generate a first growth source gas, and allowing the first growth source gas to enter a first gas chamber connected to the first reaction chamber.

[0024] S12: Introduce a second reaction gas into the second reaction chamber, so that the growth material reacts with the second reaction gas in the second reaction chamber to generate a second growth source gas, and the second growth source gas enters a second gas chamber connected to the second reaction chamber.

[0025] In some preferred embodiments, the first reaction gas includes a carrier gas and HCl, and the second reaction gas includes a carrier gas and CL2.

[0026] In some preferred embodiments, the first growth source gas includes GaCl and the second growth source gas includes GaCl3.

[0027] Furthermore, the temperature of the first growth source gas is 800-900°C, and the temperature of the second growth source gas is 1200-1400°C.

[0028] In some preferred embodiments, in order to minimize the thermal expansion of the third gas, the third gas is an inert gas with a thermal expansion coefficient of less than 0.001 / °C, and the inert gas includes nitrogen, helium or argon.

[0029] In some preferred embodiments, the growth raw materials include gallium liquid and aluminum liquid.

[0030] A third aspect of the present invention provides a growth source generating device, comprising:

[0031] The aforementioned automatic adding device for the growth material;

[0032] A growth material storage chamber, connected to the growth material automatic adding device, for storing growth materials;

[0033] At least two reaction chambers are connected to the growth material storage chamber and are used to generate growth sources based on the growth material; wherein the growth source includes the first growth source gas and the second growth source gas.

[0034] In some embodiments, the at least two reaction chambers include a first reaction chamber and a second reaction chamber, the first gas chamber is connected to the first reaction chamber, and the second gas chamber is connected to the second reaction chamber.

[0035] The growth source generating device further includes a first air inlet channel and a second air inlet channel. The first air inlet channel is used to transmit the first reaction gas to the first reaction chamber, and the second air inlet channel is used to transmit the second reaction gas to the second reaction chamber.

[0036] Furthermore, the first growth source gas is a reaction product of the growth material in the first reaction chamber and the first reaction gas; the second growth source gas is a reaction product of the growth material in the second reaction chamber and the second reaction gas.

[0037] In some embodiments, the growth source generating device further includes a first conveying channel and a second conveying channel, the first reaction chamber includes a first growth container, the second reaction chamber includes a second growth container, and the growth raw materials are transferred into the first growth container and the second growth container along the first conveying channel and the second conveying channel respectively.

[0038] In some preferred embodiments, the first growth container and the second growth container are bowl-shaped structures.

[0039] In some embodiments, the growth source generating device also includes a first valve and a second valve, the first valve is arranged on the first delivery channel, and the first valve is used to control the connection and disconnection between the first delivery channel and the first growth container, thereby controlling the delivery of the growth material; the second valve is arranged on the second delivery channel, and the second valve is used to control the connection and disconnection between the second delivery channel and the second growth container, thereby controlling the delivery of the growth material.

[0040] In some embodiments, the growth source generating device further includes a first channel and a second channel, the first air chamber is connected to the first reaction chamber through the first channel, the second air chamber is connected to the second reaction chamber through the second channel, the first channel is provided with a third valve, and the third valve is used to control the connection and disconnection between the first air chamber and the first reaction chamber; the second channel is provided with a fourth valve, and the fourth valve is used to control the connection and disconnection between the second air chamber and the second reaction chamber.

[0041] A fourth aspect of the present invention provides a growth system, which includes a crystal growth device and the aforementioned growth source generating device, wherein the growth source generating device is connected to the crystal growth area of ​​the crystal growth device.

[0042] In some embodiments, the crystal growth device includes a tray, a first output channel and a second output channel. The tray is arranged in the crystal growth area, and the tray is used to fix the seed crystal, and the seed crystal is placed vertically; wherein the first growth source output from the first output channel enters the first side of the seed crystal, and the second growth source output from the second output channel enters the second side of the seed crystal.

[0043] In some embodiments, the crystal growth apparatus further includes a first input channel and a second input channel, and the first input channel and the second input channel are used to transmit a Group V source (eg, transmitting NH3 to grow GaN) to the crystal growth region.

[0044] Compared with the prior art, the technical solution of the present invention has at least the following advantages:

[0045] (1) The automatic growth material adding device provided by the present invention includes a conveying channel, a first air chamber, a second air chamber and a third air chamber. Through the coordination among them and the control of temperature, the growth material can be automatically added to the corresponding reaction chamber, which is convenient for the subsequent generation of corresponding growth source gas in different reaction chambers to supplement the growth source gas to the crystal growth device, so as to achieve efficient and continuous growth of crystals without manual addition of growth material. The growth material can be added accurately, efficiently and automatically during the preparation process of the growth source, and has the advantages of simple structure, automatic operation and good controllability.

[0046] (2) The provided growth source generating device can automatically add growth materials in two different growth modes at the same time and the time is controllable. The continuous automatic addition of growth materials is helpful to maintain the liquid level in the growth container, so that the conversion rate of the two growth sources does not change with time during the reaction, thereby ensuring the quality of the grown crystals.

[0047] (3) The growth system provided can realize the simultaneous growth of crystals on both sides of the seed crystal in two modes. It can also use the residual heat as power to add growth raw materials or transport growth sources to the crystal growth area. By controlling the temperature field of each growth source and the concentration field and flow field above the tray, the uniformity of crystal growth and doping uniformity can be improved, which is conducive to the efficient and continuous preparation of high-quality products. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0049] Figure 1is a schematic structural diagram of a growth system in Example 1 of the present invention;

[0050] Figure 2 This is a schematic diagram of the structure of the growth system in Example 2 of the present invention.

[0051] Figure markings: 1: first reaction chamber, 101: first growth container, 102: first air inlet channel, 2: second reaction chamber, 201: second growth container, 202: second air inlet channel, 3: growth material storage chamber, 301: first delivery channel, 302: second delivery channel, 303: first valve, 304: second valve, 4: first gas chamber, 401: first channel, 402: third valve, 5: second gas chamber, 501: second channel, 502: fourth valve, 6: third gas chamber, 601: gas circulation pipeline, 7: movable baffle, 8: crystal growth area, 801: first output channel, 802: second output channel, 803: fifth valve, 804: sixth valve, 805: tray, 806: first input channel, 807: second input channel, 9: seed crystal. DETAILED DESCRIPTION

[0052] The present invention will be more fully understood by reading the following specific embodiments. However, it should be understood that the specific embodiments disclosed below are only exemplary of the present invention, and the present invention can be embodied in various forms. Therefore, the specific functional details disclosed herein should not be interpreted as limiting, but only as the basis for the claims and as a representative basis for teaching those skilled in the art to adopt the present invention in different ways in any appropriate detailed embodiment.

[0053] Some embodiments of the present invention provide an automatic growth material adding device comprising: a conveying channel, a first air chamber, a second air chamber and a third air chamber.

[0054] The first gas chamber is used for containing a first growth source gas.

[0055] The second gas chamber is thermally connected to the first gas chamber and is used for accommodating a second growth source gas.

[0056] The third gas chamber is arranged adjacent to the first gas chamber, is communicated with the growth material storage chamber, and is used for accommodating a third gas.

[0057] Among them, when the temperature of the second growth source gas in the second air chamber is higher than the temperature of the first growth source gas in the first air chamber, the first air chamber enters an expansion state and squeezes the third air chamber, so that at least part of the third gas in the third air chamber enters the growth material storage chamber and applies pressure to the growth material therein, thereby driving at least part of the growth material therein to transfer along the transport channel into at least two reaction chambers.

[0058] In some embodiments, the first air chamber and the third air chamber are sealed and isolated from each other via a movable baffle or an elastic membrane.

[0059] In some embodiments, the third air chamber is disposed between the first air chamber and the second air chamber, or the second air chamber is disposed adjacent to the first air chamber.

[0060] In some preferred embodiments, the adjacent second air chamber and the first air chamber are sealed and isolated from each other via a heat-conducting baffle.

[0061] In some embodiments, the first growth source gas includes GaCl and the second growth source gas includes GaCl3.

[0062] In some embodiments, in order to minimize the thermal expansion of the third gas, the third gas is an inert gas having a thermal expansion coefficient of less than 0.001 / °C.

[0063] In some embodiments, the temperature of the first growth source gas is 800-900°C, for example, 800°C, 810°C, 820°C, 830°C, 840°C, 850°C, 860°C, 870°C, 880°C, 890°C, or 900°C.

[0064] In some embodiments, the temperature of the second growth source gas is 1200-1400°C, for example, 1200°C, 1220°C, 1240°C, 1260°C, 1280°C, 1300°C, 1320°C, 1340°C, 1360°C, 1380°C or 1400°C.

[0065] The automatic growth material adding device designed by the present invention utilizes the temperature difference between the first growth source gas and the second growth source gas to cause the first growth source gas with a lower temperature to expand due to heat, thereby pushing the third gas in the adjacent third gas chamber into the growth material storage chamber to press out the growth material, thereby realizing automatic addition of growth material to the growth container in the reaction chamber. Moreover, the first growth source gas is different from the second growth source gas, and different growth sources can be provided to the reaction chamber, so that the growth source can be automatically added in two growth modes, thereby realizing efficient and continuous growth of the corresponding semiconductor film layer.

[0066] In some embodiments, the growth material includes gallium liquid or aluminum liquid; when the growth material is aluminum liquid, the semiconductor film layer can be an AlN crystal. When the growth material is gallium liquid, the first growth source gas is GaCl gas, the second growth source gas is GaCl3 gas, and the semiconductor film layer can be a GaN crystal. The automatic growth material adding device of the present invention is used to prepare the growth source GaCl / GaCl3 required for GaN crystals, and can accurately, efficiently and automatically realize the addition of gallium liquid in two growth modes, thereby realizing efficient and continuous growth of GaN crystals.

[0067] As another aspect of the technical solution of the present invention, a method for automatically adding growth materials is implemented based on the aforementioned automatic growth material adding device, and the method comprises:

[0068] A first growth source gas and a second growth source gas are respectively input into the first air chamber and the second air chamber; wherein the temperature of the second growth source gas is higher than that of the first growth source gas, and the second air chamber is thermally connected to the first air chamber, so that the first air chamber enters an expansion state and squeezes a third air chamber adjacent to the first air chamber, so as to drive at least part of the third gas in the third air chamber to enter the growth material storage chamber and apply pressure to the growth material therein, thereby driving at least part of the growth material therein to transfer along the transport channel into at least two reaction chambers.

[0069] In some embodiments, the method of automatically adding growth materials further comprises the steps of:

[0070] S11: introducing a first reaction gas into the first reaction chamber, allowing the growth material to react with the first reaction gas in the first reaction chamber to generate a first growth source gas, and allowing the first growth source gas to enter a first gas chamber connected to the first reaction chamber.

[0071] S12: Introduce a second reaction gas into the second reaction chamber, so that the growth material reacts with the second reaction gas in the second reaction chamber to generate a second growth source gas, and the second growth source gas enters a second gas chamber connected to the second reaction chamber.

[0072] In some preferred embodiments, the first reaction gas comprises a carrier gas and HCl, and the second reaction gas comprises a carrier gas and Cl2.

[0073] In some preferred embodiments, the first growth source gas includes GaCl and the second growth source gas includes GaCl3.

[0074] Furthermore, the temperature of the first growth source gas is 800-900°C, and the temperature of the second growth source gas is 1200-1400°C.

[0075] In some preferred embodiments, in order to minimize the thermal expansion of the third gas, the third gas is an inert gas with a thermal expansion coefficient of less than 0.001 / °C, and the inert gas includes nitrogen, helium or argon.

[0076] In some preferred embodiments, the growth feedstock includes liquid gallium and liquid aluminum.

[0077] As another aspect of the technical solution of the present invention, a growth source generating device is provided, which includes: the aforementioned automatic growth material adding device, a growth material storage chamber and at least two reaction chambers.

[0078] The growth material storage chamber is communicated with the growth material automatic adding device, and is used for storing the growth material.

[0079] Each reaction chamber is connected to a growth material storage chamber, and is used to generate a growth source based on the growth material; wherein the growth source includes a first growth source gas and a second growth source gas.

[0080] In some embodiments, the at least two reaction chambers include a first reaction chamber and a second reaction chamber, the first gas chamber is in communication with the first reaction chamber, and the second gas chamber is in communication with the second reaction chamber.

[0081] The growth source generating device further includes a first air inlet channel and a second air inlet channel. The first air inlet channel is used to transmit the first reaction gas to the first reaction chamber, and the second air inlet channel is used to transmit the second reaction gas to the second reaction chamber.

[0082] Furthermore, the first growth source gas is a reaction product of the growth material in the first reaction chamber and the first reaction gas; the second growth source gas is a reaction product of the growth material in the second reaction chamber and the second reaction gas.

[0083] In some embodiments, the growth source generating device further includes a first conveying channel and a second conveying channel, the first reaction chamber includes a first growth container, the second reaction chamber includes a second growth container, and the growth raw materials are transferred into the first growth container and the second growth container along the first conveying channel and the second conveying channel respectively.

[0084] In some preferred embodiments, the first growth container and the second growth container are bowl-shaped structures. The bowl-shaped design can increase the liquid surface area of ​​the growth raw material (e.g., gallium liquid or aluminum liquid) in the container, meet the larger contact area between the reaction gas and the growth raw material, reduce the liquid level drop speed, maintain the liquid level height, and help increase the contact time between the reaction gas and the growth raw material, improve the reaction efficiency, and thus improve the conversion rate of the growth source (e.g., the growth source GaCl and GaCl3 corresponding to the GaN crystal).

[0085] In some embodiments, the growth source generating device also includes a first valve and a second valve, the first valve is arranged on the first delivery channel, and the first valve is used to control the connection and disconnection between the first delivery channel and the first growth container, thereby controlling the delivery of the growth material; the second valve is arranged on the second delivery channel, and the second valve is used to control the connection and disconnection between the second delivery channel and the second growth container, thereby controlling the delivery of the growth material.

[0086] In some embodiments, the growth source generating device also includes a first channel and a second channel, the first air chamber is connected to the first reaction chamber through the first channel, the second air chamber is connected to the second reaction chamber through the second channel, the first channel is provided with a third valve, the third valve is used to control the connection and disconnection of the first air chamber and the first reaction chamber; the second channel is provided with a fourth valve, the fourth valve is used to control the connection and disconnection of the second air chamber and the second reaction chamber.

[0087] In one embodiment, taking gallium liquid as the growth raw material as an example, the growth source generating device provided by the present invention introduces the reaction mode of Cl2 and metallic gallium into the existing HVPE gallium boat design, and prepares the growth sources GaCl and GaCl3 corresponding to the GaN crystal respectively through two reaction chambers, which can simultaneously meet the automatic addition of gallium liquid under two different growth modes; moreover, multiple valves are provided, and by controlling each valve, the time of adding gallium liquid can be accurately controlled, and the gallium liquid can be replenished to the reaction chamber in time, so as to continuously prepare GaCl and GaCl3, which is conducive to the subsequent stable growth of GaN crystals using GaCl and GaCl3.

[0088] As another aspect of the technical solution of the present invention, a growth system is involved, which includes a crystal growth device and the aforementioned growth source generating device, wherein the growth source generating device is connected to a crystal growth region of the crystal growth device.

[0089] In some embodiments, the crystal growth device includes a tray, a first output channel and a second output channel. The tray is arranged in the crystal growth area, and the tray is used to fix the seed crystal, and the seed crystal is placed vertically; wherein the first growth source output from the first output channel enters the first side of the seed crystal, and the second growth source output from the second output channel enters the second side of the seed crystal.

[0090] Furthermore, the growth raw material is gallium liquid, the first growth source gas includes GaCl, and the first surface can be a Ga surface; the second growth source gas includes GaCl3, and the second surface can be an N surface.

[0091] In some embodiments, the crystal growth device further includes a first input channel and a second input channel, and the first input channel and the second input channel are used to transmit other growth sources to the crystal growth region, such as: a group V source, and the group V source can be NH3 to grow GaN.

[0092] The growth system provided by the present invention can grow GaN crystals in two modes. The first reaction chamber and the second reaction chamber can continuously provide growth sources GaCl and GaCl3 to the crystal growth zone respectively, so as to realize the simultaneous growth of GaN on the gallium surface and the nitrogen surface, thereby obtaining high-quality gallium nitride crystals; and when the process conditions are turned on to grow GaN crystals, it is beneficial to maintain the growth temperature, and effectively avoid the change of the GaN interface layer caused by the cooling when the metal gallium is artificially added, which affects the product quality.

[0093] The present invention is further described below by taking the growth system of gallium nitride as an example, but the present invention is not limited to the scope of the examples. The reagents and raw materials used in the following examples are all commercially available, and the test methods without specific conditions are usually carried out under conventional conditions or under conditions recommended by the manufacturers.

[0094] Example 1

[0095] like Figure 1 As shown, a growth system provided in this embodiment includes a crystal growth device and a growth source generating device, the crystal growth device includes a crystal growth area 8, the growth source generating device is connected to the crystal growth area 8, the growth source generating device includes an automatic growth material adding device, a first reaction chamber 1, a second reaction chamber 2 and a growth material storage chamber 3.

[0096] The automatic growth material adding device includes a sealed box body, and three air chambers are arranged inside the box body: a first air chamber 4, a second air chamber 5 and a third air chamber 6. The first air chamber 4 is used to accommodate the first growth source gas (i.e., GaCl); the second air chamber 5 is thermally connected to the first air chamber 4 and is used to accommodate the second growth source gas (i.e., GaCl3); the third air chamber 6 is arranged adjacent to the first air chamber 4 and is connected to the growth material storage chamber 3, and the third air chamber 6 is used to accommodate the third gas.

[0097] Furthermore, since the third air chamber 6 is disposed between the first air chamber 4 and the second air chamber 5 , the third gas filled in the third air chamber 6 is set to be an inert gas with a thermal expansion coefficient of 0.001 / ° C. to ensure that the third gas is not subject to thermal expansion as much as possible.

[0098] Furthermore, the first air chamber 4, the third air chamber 6, and the second air chamber 5 can be arranged in sequence along the length direction of the box. The box can be made of a heat-conducting material to achieve heat conduction between the first air chamber 4 and the second air chamber 5. Alternatively, the box can also be made of a heat-insulating material, and the first air chamber 4 and the second air chamber 5 can be connected by a metal or non-metal (such as carbon material) heat-conducting sheet, heat-conducting strip, heat-conducting film, or a circulating heat-conducting medium flow channel extending from the second air chamber 5 to the first air chamber 4.

[0099] In one embodiment, the first air chamber 4 and the third air chamber 6 are sealed and isolated from each other via a movable baffle 7, and the movable baffle 7 can move back and forth in the box along the length direction of the box. The movable baffle 7 can be made of a heat-conducting material such as metal or carbon, or a heat-insulating material such as silicon nitride. In some cases, the first air chamber 4 and the third air chamber 6 can also be sealed and isolated from each other via a heat-insulating or heat-conducting elastic membrane (such as a silicone rubber membrane) or other structures that can be deformed under gas pressure. The second air chamber 5 and the third air chamber 6 can be sealed and isolated from each other via a fixedly arranged heat-conducting or heat-insulating baffle, which can be made of a heat-conducting material such as metal or carbon, or a heat-insulating baffle can be made of a heat-insulating material such as silicon nitride.

[0100] The first reaction chamber 1 is connected to the first gas inlet channel 102 and the automatic growth material adding device to receive the first reaction gas delivered by the first gas inlet channel 102. The first reaction gas includes HCl and a carrier gas, and the carrier gas includes N2 and H2. A first growth container 101 is arranged in the first reaction chamber 1. The first growth container 101 can be a gallium boat and has a bowl-shaped structure.

[0101] The second reaction chamber 2 is connected to the second gas inlet channel 202 and the automatic growth material adding device to receive the second reaction gas delivered by the second gas inlet channel 202. The second reaction gas includes Cl2 and a carrier gas. The carrier gas includes N2 and H2. A second growth container 201 is arranged in the second reaction chamber 2. The second growth container 201 can be a gallium boat and has a bowl-shaped structure.

[0102] In one embodiment, the automatic growth material adding device of this embodiment also includes a first delivery channel 301 having a first valve 303 and a second delivery channel 302 having a second valve 304. The first delivery channel 301 is used to deliver the gallium liquid in the growth material storage chamber 3 into the first growth container 101, and the second delivery channel 302 is used to deliver the gallium liquid in the growth material storage chamber 3 into the second growth container 201.

[0103] It is worth noting that, normally, the first valve 303 and the second valve 304 are in an open state. When the growth source generating device needs to be controlled separately, the first valve 303 and the second valve 304 can be opened or closed as needed.

[0104] In one embodiment, the growth source generating device further includes a first channel 401, a second channel 501 and a gas circulation pipeline 501, a third valve 402 is provided on the first channel 401, and the first gas chamber 4 is connected to the first reaction chamber 1 through the first channel 401 having the third valve 402; a fourth valve 502 is provided on the second channel 501, and the second gas chamber 5 is connected to the second reaction chamber 2 through the second channel 501 having the fourth valve 502. The third gas chamber 6 is connected to the growth material storage chamber 3 through the gas circulation pipeline 601.

[0105] In this embodiment, the first reaction gas reacts with gallium in the first growth container 101 in the first reaction chamber 1 to generate the first growth source gas GaCl, and the first growth source gas GaCl enters the first gas chamber 4 along the first channel 401. The second reaction gas reacts with gallium in the second growth container 201 in the second reaction chamber 2 to generate the second growth source gas GaCl3, and the second growth source gas GaCl3 enters the second gas chamber 5 along the second channel 501.

[0106] Since the temperature of the first gas chamber 4 is 850°C and the temperature of the second gas chamber 5 is 1300°C, the temperature of the second growth source gas GaCl3 in the second gas chamber 5 is higher than the temperature of the first growth source gas GaCl in the first gas chamber 4. Due to the temperature difference, the first gas chamber 4 enters an expansion state and pushes the movable baffle 7 to move, thereby squeezing the third gas chamber 6, so that the third gas in the third gas chamber 6 enters the growth raw material storage chamber 3 and applies pressure to the gallium liquid therein, thereby driving the gallium liquid therein along the conveying channel into the gallium boat in the first reaction chamber 1 and / or the second reaction chamber 2.

[0107] In addition, the crystal growth device includes a tray 805, a first output channel 801, a second output channel 802, a first input channel 806 and a second input channel 807. The tray 805 is used to accommodate the seed crystal 9. The first output channel 801 is provided with a fifth valve 803, and the second output channel 802 is provided with a sixth valve 804. The first reaction chamber 1 is connected to the crystal growth area 8 via the first output channel 801 having the fifth valve 803, and the second reaction chamber 2 is connected to the crystal growth area 8 via the second output channel 802 having the sixth valve 804. The first input channel 806 and the second input channel 807 are used to transmit NH3 to the crystal growth area to grow GaN.

[0108] Further, the crystal growth apparatus may be a HVPE device.

[0109] In this embodiment, the first valve 303 to the sixth valve 804 may be made of high temperature resistant quartz valves.

[0110] The growth source generating device of this embodiment can simultaneously meet the requirements of automatically adding metal gallium in two different growth modes, which is described in detail below.

[0111] The group III source required for mode 1 growth is GaCl. HCl reacts with metal gallium to generate GaCl in the first reaction chamber. The temperature is controlled at 850°C. The following chemical reactions occur in the first reaction chamber:

[0112] 2HCl+2Ga==2GaCl+H2

[0113] The III-group source required for mode 2 growth is GaCl3. In the second reaction chamber, Cl2 reacts with metal gallium to generate GaCl3. The following chemical reaction occurs in the second reaction chamber:

[0114] 3Cl2+2Ga=2GaCl3

[0115] In the dual growth mode system, since the two growth modes require different temperatures, that is, there is a temperature difference between the two, two independent closed boxes are designed using this feature. The left side is the first gas chamber (i.e., the gas box containing GaCl), with a temperature of 850°C, and the right side is the second gas chamber (i.e., the gas box containing GaCl3), with a temperature difference of 450°C. At this time, the GaCl gas on the left will expand due to the heat, and the first gas chamber begins to expand and compress the inert gas in the third gas chamber located in the middle area, thereby squeezing the gallium liquid in the growth raw material storage chamber into the gallium boats in the first reaction chamber and the second reaction chamber, thereby realizing automatic addition of gallium liquid.

[0116] When there is little gallium liquid remaining in the gallium boat in the growth source generating device, the third valve and the fourth valve need to be opened for a certain period of time, so that the gallium liquid can be pushed from the growth material storage chamber into the gallium boat to replenish the gallium liquid.

[0117] When gallium liquid is added to the growth material storage chamber, the output channel of the III-group source gas (GaCl, GaCl3) entering the crystal growth device is closed, that is, the fifth valve and the sixth valve are closed, and the third valve and the fourth valve are opened; after the gallium liquid is added, the output channel is opened again. The time of the output channel switch can be accurately calculated by the following method:

[0118] W=P*(V2-V1)=n*R*(T2-T1), P=ρ*g*H

[0119] Among them, W is the gas expansion work, ρ is the density of gallium liquid, g is the gravitational acceleration, H is the falling height of gallium liquid; n is the amount of inert gas; R is the gas constant of inert gas, which is a known quantity; T1 and T2 are temperatures.

[0120] Therefore, ΔV=V2-V1 can be calculated; since V=Q*t, by setting a fixed Q (flow rate per second) through the flow controller, the time t required for each addition of gallium liquid can be accurately obtained.

[0121] The calculation formula of t is as follows:

[0122]

[0123] Among them, T GaCl 850℃, T GaCl3 It is 1300℃, and the unit of t is s.

[0124] By adjusting the ratio of nitrogen to hydrogen in GaCl / H2 / N2 and GaCl3 / H2 / N2, it is possible to continuously add gallium liquid to the gallium boat with sufficient power (expansion work).

[0125] It is worth noting that when the growth temperature remains unchanged, the third valve and the fourth valve are closed during the growth of GaN crystals and will not affect the continued growth of GaN. In addition, the temperature fluctuation caused by the artificial addition of metal gallium is large, and the GaN interface layer will change after cooling. Therefore, the impact of automatic addition of metal gallium is much smaller than that of artificial addition of metal gallium and then continued growth.

[0126] After completing the replenishment of gallium liquid, the third valve and the fourth valve can be closed, and the process conditions for growing gallium nitride crystals can be set. The fifth valve and the sixth valve connected to the crystal growth area are opened, the third valve and the fourth valve are opened, and the first valve and the second valve are closed to start growing GaN crystals.

[0127] The GaCl produced in the first reaction chamber can be used as a raw material for growing GaN on the Ga surface. The following reactions occur in the crystal growth zone:

[0128] GaCl+NH3=GaN+HCl+H2

[0129] The GaCl3 produced in the second reaction chamber can be used as a raw material for growing GaN on the N-face. The following reactions occur in the crystal growth zone:

[0130] GaCl3+NH3=GaN+3HCl

[0131] In the preparation process of GaN crystals, this embodiment can accurately, efficiently and automatically realize the addition of gallium liquid. Since the first gas chamber, the third gas chamber and the second gas chamber are integrated and designed inside a box, the structure is simple and the equipment is easy to install. By arranging the first to sixth valves in the pipeline, the addition of various growth raw materials and the start and end of the reaction in the preparation device can be regulated, and the production preparation process is controllable; and the residual heat can be used as a power to transport the III group source to the crystal growth area. By controlling the temperature field of each III group source and the concentration field and flow field above the growth sample tray, the uniformity of GaN crystal growth and doping uniformity can be improved, which is suitable for preparing high-quality gallium nitride crystals.

[0132] Example 2

[0133] like Figure 2As shown, the growth system provided in this embodiment is basically the same as that in Embodiment 1, except that: the second air chamber 5 in the automatic growth material adding device is disposed adjacent to the first side of the first air chamber 4, and the third air chamber 6 is disposed adjacent to the second side of the first air chamber 4, and the first side and the second side are adjacent sides or opposite sides. For example, if the first air chamber 4 is set to be a rectangular parallelepiped, and the first side is set to be its right side, then the second side can be its left side, upper side or lower side.

[0134] The preparation device of this embodiment can simultaneously meet the requirements of automatically adding metal gallium in two different growth modes.

[0135] In this embodiment, the first reaction gas and the metal gallium undergo a first reaction in the first reaction chamber 1 to generate a first growth source gas GaCl, which enters the first gas chamber 4 through a first channel 401 having a third valve 402; the second reaction gas and the metal gallium undergo a second reaction in the second reaction chamber 2 to generate a second growth source gas GaCl3, which enters the second gas chamber 5 through a second channel 501 having a fourth valve 502. Since the growth temperature of the first growth source gas GaCl is 850° C. and the growth temperature of the second growth source gas GaCl3 is 1300° C., the temperature of the second gas chamber 5 is set higher than the temperature of the first gas chamber 4. Due to the temperature difference, the first gas chamber 4 enters an expansion state and pushes the movable baffle 7 to move, thereby squeezing the third gas chamber 6, so that part of the third gas in the third gas chamber 6 enters the growth material storage chamber 3 and applies pressure to the gallium liquid therein, thereby driving the gallium liquid therein along the delivery channel into the gallium boat in the first reaction chamber 1 and / or the second reaction chamber 2.

[0136] Referring to Example 1, the addition of various raw materials and the start and end of the reaction in the preparation device can be regulated by setting the first to sixth valves. The specific content is similar to Example 1 and will not be repeated here.

[0137] In this embodiment, the second air chamber is disposed adjacent to the first air chamber, which can improve the heat conduction efficiency between the two and reduce heat transfer losses.

[0138] In summary, the growth system provided in this embodiment can simultaneously meet the requirements of automatic addition of gallium liquid in two different growth modes with controllable time, ensure that HCl / Cl2 and metal gallium have a large contact area, improve reaction efficiency, thereby improving the conversion rate of GaCl and GaCl3, and achieving efficient and continuous growth of GaN crystals. Moreover, compared with the reaction mode of introducing Cl2 and metal gallium in the traditional HVPE gallium boat design, the solution provided in this embodiment requires a higher temperature, can achieve the growth of GaN on the N polar surface, can improve the polarization effect, so that the N polar surface can grow planar GaN, and the Ga surface can grow hexagonal pyramid-shaped GaN, which can make the GaN crystal work at a higher frequency and broaden the scope of application.

[0139] In addition, the inventors of this case also referred to the aforementioned embodiments and conducted experiments with other raw materials, process operations, and process conditions described in this specification, and obtained relatively ideal results.

[0140] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A device for automatically adding growth materials, characterized in that: include: Conveying channel; A first gas chamber, which is used to accommodate a first growth source gas; a second gas chamber, which is thermally connected to the first gas chamber and is used to contain a second growth source gas; wherein the second growth source gas is different from the first growth source gas; a third gas chamber, which is disposed adjacent to the first gas chamber and communicated with the growth material storage chamber and is used to contain a third gas; Among them, when the temperature of the second growth source gas in the second gas chamber is higher than the temperature of the first growth source gas in the first gas chamber, the first gas chamber enters an expansion state and squeezes the third gas chamber, so that at least part of the third gas in the third gas chamber enters the growth raw material storage chamber and applies pressure to the growth raw material therein, thereby driving at least part of the growth raw material therein to transfer along the transport channel into at least two reaction chambers.

2. The automatic growth material adding device according to claim 1, characterized in that: The first air chamber and the third air chamber are sealed and isolated from each other via a movable baffle or an elastic membrane; And / or, the third air chamber is arranged between the first air chamber and the second air chamber, or the second air chamber is arranged adjacent to the first air chamber; Preferably, the adjacent second air chamber and the first air chamber are sealed and isolated from each other via a heat-conducting baffle; And / or, the first growth source gas includes GaCl; and / or, the second growth source gas includes GaCl3; and / or, the third gas is an inert gas having a thermal expansion coefficient of less than 0.001 / °C; and / or, the temperature of the first growth source gas is 800-900°C; and / or, the temperature of the second growth source gas is 1200-1400°C; and / or, the growth raw material includes gallium liquid.

3. A method for automatically adding growth materials, characterized in that: The method is implemented based on the automatic growth material adding device according to claim 1 or 2, and the method comprises: A first growth source gas and a second growth source gas are respectively input into the first air chamber and the second air chamber; wherein the second growth source gas is different from the first growth source gas, and the temperature of the second growth source gas is higher than that of the first growth source gas, and the second air chamber is thermally connected to the first air chamber, so that the first air chamber enters an expanded state and squeezes the third air chamber adjacent to the first air chamber, so as to drive at least part of the third gas in the third air chamber to enter the growth material storage chamber and apply pressure to the growth material therein, thereby driving at least part of the growth material therein to transfer along the transport channel into at least two reaction chambers.

4. The method according to claim 3, characterized in that The method further comprises: Introducing a first reaction gas into the first reaction chamber, allowing the growth raw material to react with the first reaction gas in the first reaction chamber to generate a first growth source gas, and allowing the first growth source gas to enter the first gas chamber connected to the first reaction chamber; Introducing a second reaction gas into the second reaction chamber, allowing the growth raw material to react with the second reaction gas in the second reaction chamber to generate the second growth source gas, and allowing the second growth source gas to enter the second gas chamber connected to the second reaction chamber; Preferably, the first reaction gas includes a carrier gas and HCl; and / or, the second reaction gas includes a carrier gas and Cl2; and / or, the first growth source gas includes GaCl; and / or, the third gas is an inert gas having a thermal expansion coefficient of less than 0.001 / °C; and / or, the temperature of the first growth source gas is 800-900°C; and / or, the temperature of the second growth source gas is 1200-1400°C; and / or, the growth raw material includes gallium liquid.

5. A growth source generating device, characterized in that: include: The automatic adding device for growing raw materials according to claim 1 or 2; A growth material storage chamber, connected to the growth material automatic adding device, for storing growth materials; At least two reaction chambers are connected to the growth material storage chamber and are used to generate growth sources based on the growth material; wherein the growth source includes the first growth source gas and the second growth source gas.

6. The growth source generating device according to claim 5, characterized in that: The at least two reaction chambers include a first reaction chamber and a second reaction chamber, the first gas chamber is connected to the first reaction chamber, and the second gas chamber is connected to the second reaction chamber; The growth source generating device further comprises a first air inlet channel and a second air inlet channel, wherein the first air inlet channel is used to transmit the first reaction gas to the first reaction chamber, and the second air inlet channel is used to transmit the second reaction gas to the second reaction chamber; The first growth source gas is a reaction product of the growth material in the first reaction chamber and the first reaction gas; the second growth source gas is a reaction product of the growth material in the second reaction chamber and the second reaction gas.

7. The growth source generating device according to claim 6, characterized in that: The growth source generating device further comprises a first conveying channel and a second conveying channel, the first reaction chamber comprises a first growth container, the second reaction chamber comprises a second growth container, and the growth raw materials are transferred into the first growth container and the second growth container along the first conveying channel and the second conveying channel respectively; Preferably, the first growth container and the second growth container are bowl-shaped structures.

8. The growth source generating device according to claim 7, characterized in that: The growth source generating device further comprises a first valve and a second valve, wherein the first valve is arranged on the first conveying channel, and is used to control the connection and disconnection between the first conveying channel and the first growth container, thereby controlling the conveyance of the growth material; the second valve is arranged on the second conveying channel, and is used to control the connection and disconnection between the second conveying channel and the second growth container, thereby controlling the conveyance of the growth material; And / or, the growth source generating device also includes a first channel and a second channel, the first air chamber is connected to the first reaction chamber through the first channel, the second air chamber is connected to the second reaction chamber through the second channel, the first channel is provided with a third valve for controlling the connection and disconnection of the first air chamber and the first reaction chamber; the second channel is provided with a fourth valve for controlling the connection and disconnection of the second air chamber and the second reaction chamber.

9. A growth system, comprising a crystal growth device, characterized in that: It also includes a growth source generating device as described in any one of claims 5 to 8, wherein the growth source generating device is connected to a crystal growth zone of the crystal growth device.

10. The growth system according to claim 9, characterized in that The crystal growth device includes a tray, a first output channel and a second output channel. The tray is arranged in the crystal growth area and is used to fix the seed crystal. The seed crystal is placed vertically. The first growth source output from the first output channel enters the first surface of the seed crystal, and the second growth source output from the second output channel enters the second surface of the seed crystal.

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