Method, system and terminal for prolonging single growth time of single crystal diamond

Abstract

The invention discloses a method, a system and a terminal for prolonging single growth time of single crystal diamond, and the method comprises the following steps: obtaining diamond seed crystals, putting the diamond seed crystals into a reaction cavity of MPCVD equipment, and carrying out vacuumizing treatment and glow starting treatment on the reaction cavity to obtain a first growth reaction environment of the diamond seed crystals; acquiring preset process gas, and inputting the preset process gas into the first growth reaction environment in a segmented manner according to preset concentration to obtain a second growth reaction environment; and according to the second growth reaction environment, carrying out staged heating treatment and seed crystal single growth treatment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is finished. According to the method, the concentration proportion of various process gases in the reaction cavity is slowly increased according to different time periods, so that the growth reaction environment of the diamond seed crystals is controlled, the growth time of the monocrystal diamond can be effectively prolonged, and the cultivation quality of the monocrystal diamond is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of diamond cultivation, and in particular to a method, system, terminal and computer-readable storage medium for extending the single growth time of single crystal diamond. Background Art

[0002] Diamond has attracted everyone's attention due to its extremely excellent physical and chemical properties. However, the reserves of natural diamond are limited, so people have developed a variety of synthetic diamond methods, such as high temperature and high pressure method (HPHT, High pressure High temperature), hot filament chemical vapor deposition method (HFCVD, hot filament chemical vapor deposition), etc. Among them, microwave plasma chemical vapor deposition method MPCVD, Microwave plasma chemical vapor deposition, this synthetic diamond method can synthesize high-quality and large-area diamonds without the introduction of impurities. It has the advantages of no electrode discharge pollution, fast deposition rate, good stability, etc., and is considered to be the best method for preparing high-quality single-crystal diamonds.

[0003] However, in the existing single crystal diamond growth process, due to problems such as unstable growth temperature and unreasonable gas ratio, the single crystal diamond growth time is short, and the growth quality is poor, the yield is low, and the effective growth rate is low, resulting in extremely high production costs for the grown diamond, which cannot meet the needs of large-scale mass production of single crystal grown diamond.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] The main purpose of the present invention is to provide a method, system, terminal and computer-readable storage medium for extending the single growth time of single crystal diamond, aiming to solve the problems of unstable growth temperature and unreasonable gas ratio in the single crystal diamond cultivation process in the prior art, resulting in a short single growth time of single crystal diamond, poor growth quality, low yield and low effective growth rate, which leads to extremely high production cost of cultivated diamond and cannot meet the demand for large-scale mass production of single crystal cultivated diamond.

[0006] To achieve the above object, the present invention provides a method for extending the single growth time of single crystal diamond, the method comprising the following steps:

[0007] Obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment for the diamond seed crystal;

[0008] Obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment;

[0009] According to the second growth reaction environment, a staged temperature increase treatment and a seed crystal single growth treatment are performed to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0010] Optionally, the single growth time extension method of single crystal diamond, wherein the vacuuming and ignition treatment of the reaction chamber to obtain the first growth reaction environment of the diamond seed crystal specifically includes:

[0011] Acquiring a first intra-cavity air pressure range of the reaction cavity, and using a vacuum pump to roughly pump the reaction cavity until the first intra-cavity air pressure range drops to a second intra-cavity air pressure range;

[0012] Setting a preset flow rate of hydrogen, and charging the preset flow rate of hydrogen into the reaction chamber to perform multiple iterations of cleaning treatment, and completing the vacuum treatment;

[0013] Turning on a microwave power supply, performing an ignition process on the preset flow rate hydrogen gas filled into the reaction chamber through the microwave power supply, and after the ignition process is completed, setting a first growth reaction environment for the diamond seed crystal;

[0014] The first growth reaction environment includes a preset hydrogen target flow range, a preset gas pressure range, a preset power range, and a preset crystal surface temperature of the diamond seed crystal.

[0015] Optionally, in the single growth time extension method of single crystal diamond, the preset process gas includes a first process gas, a second process gas, a third process gas and a fourth process gas;

[0016] The step of obtaining a preset process gas and inputting the preset process gas into the first growth reaction environment in sections according to a preset concentration to obtain a second growth reaction environment specifically includes:

[0017] Inputting the first process gas of a first preset concentration and the second process gas of a second preset concentration into the first growth reaction environment, and performing a first stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration;

[0018] Inputting the third process gas of a fifth preset concentration into the first growth reaction environment, and performing a second stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a sixth preset concentration and the second process gas of a seventh preset concentration;

[0019] Inputting the fourth process gas of the third preset concentration into the first growth reaction environment, and performing a third stage concentration increasing process on the first process gas and the third process gas to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration;

[0020] The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration constitute a second growth reaction environment.

[0021] Optionally, the single growth time extension method of single crystal diamond, wherein the first process gas of a first preset concentration and the second process gas of a second preset concentration are input into the first growth reaction environment, and the first process gas and the second process gas are subjected to a first stage concentration increase treatment to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration, specifically comprises:

[0022] Inputting the first process gas of the first preset concentration and the second process gas of the second preset concentration into the first growth reaction environment, and allowing the first process gas of the first preset concentration and the second process gas of the second preset concentration to stay in the first growth reaction environment for a first preset time range;

[0023] When the residence time reaches the first preset time range, the first preset concentration of the first process gas is increased to the third preset concentration, and the second preset concentration of the second process gas is increased to the fourth preset concentration;

[0024] The first process gas at the third preset concentration and the second process gas at the fourth preset concentration are kept in the first growth reaction environment for a second preset time range.

[0025] Optionally, the single growth time extension method of single crystal diamond, wherein the third process gas of the fifth preset concentration is input into the first growth reaction environment, and the first process gas and the second process gas are subjected to a second stage concentration increase treatment to obtain the first process gas of the sixth preset concentration and the second process gas of the seventh preset concentration, specifically comprises:

[0026] Inputting the third process gas of a fifth preset concentration into the first growth reaction environment;

[0027] increasing the third preset concentration of the first process gas to the sixth preset concentration, and increasing the fourth preset concentration of the second process gas to the seventh preset concentration;

[0028] The first process gas at the sixth preset concentration, the second process gas at the seventh preset concentration, and the third process gas at the fifth preset concentration are kept in the first growth reaction environment for a third preset time range.

[0029] Optionally, the single growth time extension method of single crystal diamond, wherein the fourth process gas of the third preset concentration is input into the first growth reaction environment, and the first process gas and the third process gas are subjected to a third stage concentration increase treatment to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration, specifically comprises:

[0030] Inputting the fourth process gas of the third preset concentration into the first growth reaction environment;

[0031] increasing the sixth preset concentration of the first process gas to the eighth preset concentration, and increasing the fifth preset concentration of the third process gas to the ninth preset concentration;

[0032] The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration are kept in the first growth reaction environment for a fourth preset time range.

[0033] Optionally, the method for extending the single growth time of a single crystal diamond, wherein the step of performing a staged temperature increase treatment and a single growth treatment of a seed crystal according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed, specifically comprises:

[0034] The temperature of the reaction chamber in the MPCVD device is raised in stages to obtain a second growth reaction environment with different stage temperatures;

[0035] The diamond seed crystal is subjected to a seed crystal single growth process according to the second growth reaction environment at different stage temperatures to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0036] In addition, to achieve the above-mentioned purpose, the present invention further provides a system for extending the single growth time of a single crystal diamond, wherein the system for extending the single growth time of a single crystal diamond comprises:

[0037] A first growth reaction environment generating module, used for obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment of the diamond seed crystal;

[0038] A second growth reaction environment generating module, used for obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in sections according to a preset concentration, to obtain a second growth reaction environment;

[0039] The seed crystal single growth module is used to perform a staged temperature increase process and a seed crystal single growth process according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0040] In addition, to achieve the above-mentioned purpose, the present invention also provides a terminal, wherein the terminal includes: a memory, a processor, and a single growth time extension program for single crystal diamond stored in the memory and executable on the processor, and when the single growth time extension program for single crystal diamond is executed by the processor, the steps of the single growth time extension method for single crystal diamond as described above are implemented.

[0041] In addition, to achieve the above-mentioned purpose, the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a single growth time extension program for single crystal diamond, and when the single growth time extension program for single crystal diamond is executed by a processor, the steps of the single growth time extension method for single crystal diamond as described above are implemented.

[0042] In the present invention, a diamond seed crystal is obtained, and the diamond seed crystal is placed in the reaction chamber of the MPCVD device, and the reaction chamber is vacuumed and ignited to obtain a first growth reaction environment for the diamond seed crystal; a preset process gas is obtained, and the preset process gas is input into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment; a staged temperature increase treatment and a seed crystal single growth treatment are performed according to the second growth reaction environment to obtain the target single crystal diamond after the single growth of the diamond seed crystal is completed. The present invention constructs a second growth reaction environment by inputting process gas into the reaction chamber of the MPCVD device in different time periods under the first growth reaction environment, and controlling the concentration ratio of the process gas in each time period, thereby effectively controlling the temperature change and methane ratio of the diamond seed crystal during the growth process, thereby effectively extending the single growth time of the single crystal diamond, and at the same time, effectively ensuring its growth quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a flow chart of a preferred embodiment of the method for extending the single growth time of single crystal diamond of the present invention;

[0044] Figure 2 It is a structural diagram of a preferred embodiment of a single growth time extension system for single crystal diamond of the present invention;

[0045] Figure 3 It is a structural diagram of a preferred embodiment of the terminal of the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0047] Diamond has attracted everyone's attention due to its extremely excellent physical and chemical properties. However, the reserves of natural diamond are limited, so people have developed a variety of synthetic diamond methods, such as high temperature and high pressure method (HPHT, High pressure High temperature), hot filament chemical vapor deposition method (HFCVD, hot filament chemical vapor deposition), etc. Among them, microwave plasma chemical vapor deposition method MPCVD, Microwave plasma chemical vapor deposition, this synthetic diamond method can synthesize high-quality and large-area diamonds without the introduction of impurities. It has the advantages of no electrode discharge pollution, fast deposition rate, good stability, etc., and is considered to be the best method for preparing high-quality single-crystal diamonds.

[0048] At present, the mainstream technology route for synthesizing diamonds by chemical vapor deposition is MPCVD (microwave plasma chemical vapor deposition), which is the most mature technology and the most widely used in the market. The advantages of MPCVD technology are: 1. The reaction chamber is larger, which is more suitable for cultivating large-grain diamonds; 2. No electrodes are required during the plasma generation process, and no electrode impurities will be introduced, making it easier to cultivate high-purity diamonds.

[0049] However, the existing process technology has the following defects: 1. The growth temperature is too high, and temperature mutations are prone to occur during the growth process (such as deformation of the molybdenum sheet due to high temperature, polycrystalline cracking on the surface of the molybdenum sheet, deformation of the water-cooled substrate during the growth process, etc.); 2. The temperature is unstable, and crystal defects are expressed quickly. Generally, a single growth can only be carried out for about 120-150 hours, and the growth quality is poor; 3. The methane ratio is too high, resulting in more graphite deposited on the quartz above the cavity during the growth process, about 130 hours after growth, causing the local temperature of the quartz to be too high, resulting in reddening ablation and reflection jump problems, resulting in many abnormal shutdowns.

[0050] In view of the above problems, the present invention has designed a method for extending the single growth time of single crystal diamond. By controlling the methane ratio, oxygen ratio and growth temperature, the single growth time of single crystal diamond can be extended from the previous 120-150 hours to 300-350 hours, which can mass-produce artificially cultivated diamond blanks with stable quality for a long time.

[0051] The method for extending the single growth time of single crystal diamond according to a preferred embodiment of the present invention is as follows: Figure 1 As shown, the method for extending the single growth time of single crystal diamond comprises the following steps:

[0052] Step S10, obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment for the diamond seed crystal.

[0053] Before filling the reaction chamber of the MPCVD equipment with process gas to cultivate diamond seed crystals, the reaction chamber needs to be cleaned (cleaned by filling with hydrogen). At the same time, before cleaning, the air pressure in the chamber needs to be controlled by a vacuum pump. When in a vacuum state, the reaction chamber can be cleaned multiple times by filling with hydrogen (the steps of vacuuming and filling with hydrogen for cleaning are iteratively performed, generally requiring three iterations) to ensure that the impurity gases in the reaction chamber do not affect the normal growth of diamonds.

[0054] Specifically, a first intracavity air pressure range of the reaction cavity is obtained, and a vacuum pump is used to perform a rough pumping treatment on the reaction cavity until the first intracavity air pressure range drops to a second intracavity air pressure range; a preset flow rate of hydrogen is set, and the preset flow rate of hydrogen is filled into the reaction cavity for multiple iterative cleaning treatments, and the vacuum pumping treatment is completed; a microwave power supply is turned on, and the preset flow rate of hydrogen filled into the reaction cavity is ignited by the microwave power supply, and when the ignition treatment is completed, a first growth reaction environment of the diamond seed crystal is set; wherein the first growth reaction environment includes a preset hydrogen target flow rate range, a preset air pressure range, a preset power range, and a preset crystal surface temperature of the diamond seed crystal.

[0055] The preparations before placing the diamond seed crystal into the MPCVD equipment are as follows: 1. Check whether the quartz window is normal before and after use. If there is any crack or damage, notify and replace it in time. 2. Perform a baking and pressure test on the equipment before use. The test steps are as follows: 1). Conditions for baking equipment: suitable molybdenum sheet combination, H 2 :200Sccm、O 2: 2Sccm, power: above 5500W, air pressure: 145-160Torr, temperature: 800-1000℃ (the temperature should be as high as possible) and baking time: 2-4h. 2). After baking, evacuate to the vacuum limit of the equipment (also called vacuum background), maintain this background for more than 30 minutes, and remember not to break the vacuum. Among them, the valves that need to be opened for vacuuming include: "V1", "V2", "V3", "V4" and "V5" five valves and a mechanical pump. 3). After evacuating to the background, close valves "V5" and "V1" and the mechanical pump in turn. Keep "V2", "V3" and "V4" in the open state. 4). The first type of pressure holding calculation: Click "Start" on the process timer, record the pressure holding background value (for example, the background is 5mTorr), take a photo or record it in the notebook. For short-time pressure holding, it is necessary to accurately record the time when the value jump changes (for example, the time from 5mTorr to 6mTorr is 15min30s), and the end time of the test pressure jump (pressure change ≥1mTorr) (for example, the time from 6mTorr to 11mTorr is 2h20min30s). At this time, the result of short-time pressure holding can be calculated. Generally speaking, taking the above example, if the pressure holding test fails, it is necessary to set the time after the change of the first 3-5mTorr as the start time, and the change of (1-N)mTorr (where N≥2) after the accurate test as the end time to calculate the pressure holding. The method for long-time pressure holding is the same as above, but the accurate pressure jump time is not required. Long-time pressure holding is suitable for overnight testing. 5). The second type of pressure holding calculation: The processing method is the same as above. The data of the first hour (for example, 10mTorr) of the process timer is recorded, and then the pressure holding data of the 2nd / 3rd / 4th... hour (for example: 15 / 19 / 24...) are recorded later. The more accurate pressure holding data can be roughly calculated: (24-10) / 3 is about 4.67mTorr / h. At the same time, it is also necessary to ensure that the difference between each hour is not too large. If there is a pressure holding that deviates significantly from the average value, it is considered abnormal. Under the condition of not breaking the vacuum, the specific pressure holding data per minute should be calculated according to the test method of the first pressure holding calculation. 3. Clean the water cooling table: Before placing the seed crystal or diamond sheet into the equipment, wet the water cooling table with alcohol with a dust-free cloth, wipe the door and the surrounding area of ​​the door clean. After placing the seed crystal or diamond into the equipment, wet the door and the surrounding area of ​​the door clean with a dust-free cloth.

[0056] After the diamond seed crystal is placed in the cavity, vacuuming and heating operations are performed. Under the condition of pure hydrogen (i.e., the preset flow rate hydrogen in the present invention) (hydrogen is filled at the beginning, and MPCVD equipment generally uses hydrogen as the starting gas), the air pressure is set to 175 Torr (i.e., the preset air pressure range in the present invention), and the power is set to 5300-5500W (i.e., the preset power range in the present invention), the temperature of the surface of the diamond seed crystal (the thermometer is an infrared thermometer, model COMPACT MI3) is about 780-810°C (i.e., the preset crystal surface temperature of the diamond seed crystal in the present invention), and the overall temperature difference of the diamond seed crystal is preferably not more than 30°C.

[0057] The vacuuming process is as follows: after closing the door, turn on the vacuum pump, and start rough pumping when the air pressure inside the chamber is pumped to about 50 Torr, until the air pressure in the chamber is pumped to the background vacuum, generally between 0-10mTorr, and then turn off the rough vacuum pump, set the hydrogen flow rate to 200Sccm, and when the air pressure reaches 10Torr, turn off the hydrogen flow rate, open the vacuum rough pumping pipeline again to pump to the background vacuum, and repeat this three times to clean the internal environment of the reaction chamber, clean the air and moisture inside the chamber, and achieve a relatively pure growth environment.

[0058] It can be understood that the specific operation process of vacuuming is as follows: 1. Soft-pumping air pressure: open valves "V1", "V3", "V4" and mechanical pumps to reduce the cavity air pressure from atmospheric pressure 760Torr to 15Torr, and determine that the cavity air pressure value is around 15Torr through the air pressure control target value. Among them, there will be vacuum setting parameters in the "Automatic" menu under the "Settings" of the panel. Generally, the supplier has set the "pumping speed" and "soft pumping time limit", which can automatically realize the execution process of soft pumping air pressure. 2. Rough pumping air pressure: refers to the condition that the soft pumping valve is open, and the cavity "air pressure target value" reaches 15Torr. Next, open valves "V2" and "V5", and the air pressure will decrease over time until the panel displays the "air pressure control target value" of 10mTorr. Generally, the supplier has set the "rough pumping time limit", which can automatically realize the execution process of rough pumping air pressure. 3. When the equipment turns on "water cooling", you can already press and hold the "filament" to preheat the microwave generator. It will turn on when it lights green. This step can be done before or during vacuuming. Among them, you can check the vacuum setting panel so that you can preheat the "filament" by yourself during automatic control. 4. Raise the height of the substrate stage to the starting height set by the supplier. The corresponding "substrate stage height" will be displayed on the vacuum setting panel. You can manually adjust it to the corresponding height on the "operation" panel, or you can check it during automatic control, and it will automatically rise to the corresponding height during the vacuum process.

[0059] It can be understood that cleaning the reaction chamber refers to the process of replacing the air in the chamber with hydrogen.

[0060] There are corresponding parameters in the "Automatic" column of "Settings", including "H 2 The rate of flow increase, "H 2 Maximum flow rate", "filling H 2 Air pressure", charge 2 Time", "Number of cleaning times" and "Start" which can be checked. Generally, "H 2 The rate of flow increase, "H 2 Maximum flow rate", "filling H 2 Air pressure" and "filling 2 There are four options of "cleaning times", generally speaking, the supplier will set appropriate parameters according to the mechanical pump, and you need to edit the "cleaning times" according to your own growth and deposition needs. Usually, the present invention is set to 3 times, which can meet the atmosphere environment requirements of the present invention.

[0061] The manual operation steps for cavity cleaning are as follows: "Cleaning" requires slowly passing H 2 , increase the gas pressure from 10mTorr to 10Torr, and then turn off the H 2 Open valve "V2" for rough pumping to reduce the air pressure to below 10mTorr. This process takes 3-5 minutes and needs to be repeated 3 times.

[0062] The automatic operation steps for cavity cleaning are as follows: In the supplier's settings, the two steps of "vacuuming" and "cleaning" are automatically connected as one step, that is, completing the "vacuuming" step also completes the "cleaning" step.

[0063] The process of heating the cavity is as follows: after introducing 5-10Torr of hydrogen, turn on the microwave power supply and start the glow. Specifically, when the reaction gas is ionized under the action of the microwave field, positive ions and electrons are formed. These charged particles are accelerated in the electric field and collide with gas molecules, producing more ions and electrons, and finally forming a glow discharge plasma. This phenomenon is called "starting". After the ignition is completed, the hydrogen target flow rate is set to 200-500Sccm, the gas pressure condition is 165-185Torr, the power is 5300-5500W, and the heating time is 30 minutes. After the heating is completed, the surface temperature of the diamond seed crystal should be 780-810℃.

[0064] It can be understood that the ignition includes manual ignition and automatic ignition. 1. The manual ignition operation is as follows: The conditions required for ignition are: 2 In the atmosphere, H 2The flow rate is set at 40-60Sccm, the microwave power is 600W, the gas pressure is between 5-10Torr, usually set at around 7Torr, and the substrate stage height is at the height set in the "Start" option. After these conditions are met, you can long press the "Microwave Power" button on the panel to start the start. The sign of a successful start is that white plasma is generated in the cavity less than 5mm above the substrate stage, covering the surface of the substrate stage. If it appears in other positions, the start fails. After the "Start" successfully ignites the plasma, set the panel "Gas Pressure Control Target Value" to "20Torr". At this time, you can slowly increase the H 2 The flow rate reaches 200 Sccm. Generally, this process takes 3-5 minutes. 2. The operation of automatic ignition is as follows: After the "cleaning" step of the reaction chamber is completed, long press the "ignition" button on the "operation" panel.

[0065] Heating refers to the temperature of the growing material (usually diamond) rising from room temperature to the temperature required for the process. In the "Settings", "Automatic" "Heating" column, there are corresponding parameters. Among them are "Total Time", "Step Size", "Power", "Air Pressure" and "H 2 There are editable options such as "Flow", "Target Temperature" and "Recipe" that can be checked. Heating includes manual heating and automatic heating. The steps of manual heating are as follows: Set the end conditions of "Start": 600W, 20Torr, H 2 Flow rate: 200 Sccm. Slowly change the conditions by increasing the gas pressure first and then the power. 2 The flow rate should also increase slowly. The amount of power and pressure can be increased by proportionally changing the set value according to the desired end condition or the condition under automatic setting until the required temperature or power and pressure are reached. The steps for automatic temperature rise are as follows: After the "start" is over, long press the "automatic temperature rise" button on the "operation" panel. You can set the required "total time", "step length", "power", pressure" and "H" according to your needs. 2 Flow". There are three conditions for the end of automatic heating: 1. If the "Temperature" option is checked, the temperature will be given priority. If the set temperature is reached, but the "Power" or "Air Pressure" has not reached the set value, the automatic heating will end; 2. If the "Temperature" option is checked, the temperature will be given priority. If the set temperature is not reached, but the "Power" or "Air Pressure" has reached the set value, the automatic heating will end; 3. If the "Temperature" option is not checked, the automatic heating will end when the set "Power" and "Air Pressure" values ​​are reached.

[0066] Step S20, obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment. The preset process gas includes a first process gas, a second process gas, a third process gas, and a fourth process gas.

[0067] In the present invention, the first process gas is preferably methane, the second process gas is oxygen, the third process gas is nitrogen, and the fourth process gas is argon. The input time of the process gas is processed in sections, and the flow rate of the process gas charged in each period is different, which not only realizes the normal growth of diamond, but also avoids the problem of graphite accumulation on the quartz of the reaction chamber due to excessively high methane ratio. At the same time, as the oxygen ratio increases, the graphite on the quartz can be further eliminated, ensuring the normal operation of the equipment.

[0068] Specifically, the first process gas at the first preset concentration and the second process gas at the second preset concentration are input into the first growth reaction environment, and the first process gas at the first preset concentration and the second process gas at the second preset concentration are retained in the first growth reaction environment for a first preset time range; when the residence time reaches the first preset time range, the first preset concentration of the first process gas is increased to the third preset concentration, and the second preset concentration of the second process gas is increased to the fourth preset concentration; the first process gas at the third preset concentration and the second process gas at the fourth preset concentration are retained in the first growth reaction environment for a second preset time range.

[0069] Under the conditions of constant pressure and constant power, methane (i.e., the first process gas in the present invention), oxygen (i.e., the second process gas in the present invention), nitrogen (i.e., the third process gas in the present invention), argon (i.e., the fourth process gas in the present invention) and other process gases are slowly introduced. The present invention divides the entire process gas input time into five sections. In the first five minutes, the methane concentration increases from 0 to 1% (i.e., the first preset concentration in the present invention), and the oxygen concentration is input at about 0.1% (i.e., the second preset concentration in the present invention). It is stabilized under this condition for about 5 minutes (i.e., the first preset time range in the present invention). Then, a slow ramp is set for 5 minutes, and the methane concentration increases from 1% to 2% (i.e., the third preset concentration in the present invention), and the oxygen concentration input increases from 0.1% to 0.2% (i.e., the fourth preset concentration in the present invention). It is stabilized under this atmosphere condition for about 10 minutes (i.e., the second preset time range in the present invention, maintaining a methane concentration of 2% and an oxygen concentration of 0.2% in the reaction chamber for ten minutes).

[0070] The third process gas of the fifth preset concentration is input into the first growth reaction environment; the third preset concentration of the first process gas is increased to the sixth preset concentration, and the fourth preset concentration of the second process gas is increased to the seventh preset concentration; the first process gas of the sixth preset concentration, the second process gas of the seventh preset concentration, and the third process gas of the fifth preset concentration are kept in the first growth reaction environment for a third preset time range.

[0071] After that, a slow ramp is set for 5 minutes, with the methane concentration rising from 2% to 4% (i.e., the sixth preset concentration in the present invention), the oxygen concentration rising from 0.2% to 0.4% (i.e., the seventh preset concentration in the present invention), and the nitrogen concentration rising from 0 to 0.002% (i.e., the fifth preset concentration in the present invention). The atmosphere is stabilized for about 20 minutes (i.e., the third preset time range in the present invention).

[0072] The fourth process gas at the third preset concentration is input into the first growth reaction environment; the sixth preset concentration of the first process gas is increased to the eighth preset concentration, and the fifth preset concentration of the third process gas is increased to the ninth preset concentration; the first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration are kept in the first growth reaction environment for a fourth preset time range.

[0073] Then set a slow ramp for 5 minutes, the methane concentration increased from 4% to 7% (i.e. the eighth preset concentration in the present invention), the oxygen concentration remained unchanged (maintained the seventh preset concentration, because the oxygen had reached the set value for formal growth, so there was no need to change it), the nitrogen concentration increased from 0.002% to 0.004% (i.e. the ninth preset concentration in the present invention), and the argon concentration increased from 0 to 2% (i.e. the third preset concentration in the present invention), and stabilized under this atmosphere condition for about 180 minutes.

[0074] The reason why nitrogen and argon are charged after methane and oxygen is that methane and oxygen are charged first to ensure the establishment of a relatively stable plasma environment. The active groups formed by the reaction between methane and oxygen play a vital role in the diamond nucleation period. The main functions of nitrogen and argon are to optimize the reaction conditions, adjust or stabilize the electron density of the plasma, and increase the growth rate to a certain extent. If they are added too early, the growth rate will be too fast during the early stage of diamond nucleation, which will lead to the formation of unnecessary by-products in the early stage, resulting in too many growth defects and reducing the quality of diamond.

[0075] The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration constitute a second growth reaction environment.

[0076] Step S30, performing a staged temperature increase process and a seed crystal single growth process according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0077] After the second growth reaction environment is constructed, the surface temperature of the diamond tends to be stable. After that, the present invention sets a staged temperature increase treatment. Through the temperature settings in different stages, the single growth time of the diamond can be effectively improved (it can be extended from the previous single growth time of 120-150 hours to 300-350 hours).

[0078] Specifically, the temperature inside the reaction chamber of the MPCVD device is subjected to a stage-by-stage heating treatment to obtain a second growth reaction environment with different stage temperatures; the diamond seed crystal is subjected to a seed crystal single growth treatment according to the second growth reaction environment with different stage temperatures to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0079] After 180 minutes (i.e., the fourth preset time range in the present invention), the atmosphere in the reaction chamber gradually stabilizes, and the surface temperature of the diamond crystal also tends to be relatively stable. At this time, the constant temperature is set at 880-900°C for diamond growth. The growth is carried out at 880-900°C for about 100 hours. After that, the temperature can be increased to 930°C for constant temperature growth. By analogy, the maximum temperature can be increased to 960°C. At this time, the longest growth time of diamond is about 300-350 hours.

[0080] Furthermore, if Figure 2 As shown, based on the above single crystal diamond single growth time extension method, the present invention also provides a single crystal diamond single growth time extension system, wherein the single crystal diamond single growth time extension system comprises:

[0081] A first growth reaction environment generating module 51 is used to obtain a diamond seed crystal, place the diamond seed crystal into a reaction chamber of an MPCVD device, and perform a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment of the diamond seed crystal;

[0082] A second growth reaction environment generating module 52 is used to obtain a preset process gas, and input the preset process gas into the first growth reaction environment in sections according to a preset concentration to obtain a second growth reaction environment;

[0083] The seed crystal single growth module 53 is used to perform a staged temperature increase process and a seed crystal single growth process according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0084] Furthermore, if Figure 3 As shown, based on the above-mentioned method and system for extending the single growth time of single crystal diamond, the present invention also provides a terminal accordingly, and the terminal includes a processor 10, a memory 20 and a display 30. Figure 3 Only some components of the terminal are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0085] In some embodiments, the memory 20 may be an internal storage unit of the terminal, such as a hard disk or memory of the terminal. In other embodiments, the memory 20 may also be an external storage device of the terminal, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. equipped on the terminal. Further, the memory 20 may also include both an internal storage unit of the terminal and an external storage device. The memory 20 is used to store application software and various types of data installed in the terminal, such as the program code of the installation terminal. The memory 20 may also be used to temporarily store data that has been output or is to be output. In one embodiment, a single growth time extension program 40 of single crystal diamond is stored on the memory 20, and the single growth time extension program 40 of single crystal diamond can be executed by the processor 10, thereby realizing the single growth time extension method of single crystal diamond in the present application.

[0086] In some embodiments, the processor 10 may be a central processing unit (CPU), a microprocessor or other data processing chip, used to run the program code or process data stored in the memory 20, such as executing the single growth time extension method of the single crystal diamond.

[0087] In some embodiments, the display 30 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 30 is used to display information on the terminal and to display a visual user interface.

[0088] In one embodiment, when the processor 10 executes the single growth time extension program 40 of single crystal diamond in the memory 20, the following steps are implemented:

[0089] Obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment for the diamond seed crystal;

[0090] Obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment;

[0091] According to the second growth reaction environment, a staged temperature increase treatment and a seed crystal single growth treatment are performed to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0092] The step of performing vacuum treatment and ignition treatment on the reaction chamber to obtain a first growth reaction environment for the diamond seed crystal specifically includes:

[0093] Acquiring a first intra-cavity air pressure range of the reaction cavity, and using a vacuum pump to roughly pump the reaction cavity until the first intra-cavity air pressure range drops to a second intra-cavity air pressure range;

[0094] Setting a preset flow rate of hydrogen, and charging the preset flow rate of hydrogen into the reaction chamber to perform multiple iterations of cleaning treatment, and completing the vacuum treatment;

[0095] Turning on a microwave power supply, performing an ignition process on the preset flow rate hydrogen gas filled into the reaction chamber through the microwave power supply, and after the ignition process is completed, setting a first growth reaction environment for the diamond seed crystal;

[0096] The first growth reaction environment includes a preset hydrogen target flow range, a preset gas pressure range, a preset power range, and a preset crystal surface temperature of the diamond seed crystal.

[0097] Wherein, the preset process gas includes a first process gas, a second process gas, a third process gas and a fourth process gas;

[0098] The step of obtaining a preset process gas and inputting the preset process gas into the first growth reaction environment in sections according to a preset concentration to obtain a second growth reaction environment specifically includes:

[0099] Inputting the first process gas of a first preset concentration and the second process gas of a second preset concentration into the first growth reaction environment, and performing a first stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration;

[0100] Inputting the third process gas of a fifth preset concentration into the first growth reaction environment, and performing a second stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a sixth preset concentration and the second process gas of a seventh preset concentration;

[0101] Inputting the fourth process gas of the third preset concentration into the first growth reaction environment, and performing a third stage concentration increasing process on the first process gas and the third process gas to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration;

[0102] The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration constitute a second growth reaction environment.

[0103] The step of inputting the first process gas of a first preset concentration and the second process gas of a second preset concentration into the first growth reaction environment, and performing a first-stage concentration increase treatment on the first process gas and the second process gas to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration specifically includes:

[0104] Inputting the first process gas of the first preset concentration and the second process gas of the second preset concentration into the first growth reaction environment, and allowing the first process gas of the first preset concentration and the second process gas of the second preset concentration to stay in the first growth reaction environment for a first preset time range;

[0105] When the residence time reaches the first preset time range, the first preset concentration of the first process gas is increased to the third preset concentration, and the second preset concentration of the second process gas is increased to the fourth preset concentration;

[0106] The first process gas at the third preset concentration and the second process gas at the fourth preset concentration are kept in the first growth reaction environment for a second preset time range.

[0107] The step of inputting the third process gas of the fifth preset concentration into the first growth reaction environment and performing a second-stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of the sixth preset concentration and the second process gas of the seventh preset concentration specifically includes:

[0108] inputting the third process gas of a fifth preset concentration into the first growth reaction environment;

[0109] increasing the third preset concentration of the first process gas to the sixth preset concentration, and increasing the fourth preset concentration of the second process gas to the seventh preset concentration;

[0110] The first process gas at the sixth preset concentration, the second process gas at the seventh preset concentration, and the third process gas at the fifth preset concentration are kept in the first growth reaction environment for a third preset time range.

[0111] The step of inputting the fourth process gas of the third preset concentration into the first growth reaction environment, and performing a third stage concentration increasing process on the first process gas and the third process gas to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration specifically includes:

[0112] Inputting the fourth process gas of the third preset concentration into the first growth reaction environment;

[0113] increasing the sixth preset concentration of the first process gas to the eighth preset concentration, and increasing the fifth preset concentration of the third process gas to the ninth preset concentration;

[0114] The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration are kept in the first growth reaction environment for a fourth preset time range.

[0115] The step of performing a staged temperature increase process and a single growth process of the seed crystal according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed specifically includes:

[0116] The temperature of the reaction chamber in the MPCVD device is raised in stages to obtain a second growth reaction environment with different stage temperatures;

[0117] The diamond seed crystal is subjected to a seed crystal single growth process according to the second growth reaction environment at different stage temperatures to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

[0118] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a single growth time extension program for single crystal diamond, and when the single growth time extension program for single crystal diamond is executed by a processor, the steps of the single growth time extension method for single crystal diamond as described above are implemented.

[0119] In summary, the present invention provides a method for extending the single growth time of a single crystal diamond and related equipment, the method comprising: obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment of the diamond seed crystal; obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment; performing a staged temperature increase treatment and a seed crystal single growth treatment according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed. The present invention constructs a second growth reaction environment by inputting process gas into the reaction chamber of an MPCVD device in different time periods under the first growth reaction environment, and controlling the concentration ratio of the process gas in each time period, thereby effectively controlling the temperature change and methane ratio of the diamond seed crystal during the growth process, thereby effectively extending the single growth time of the single crystal diamond, and at the same time, effectively ensuring its growth quality.

[0120] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or terminal including the element.

[0121] Of course, those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the program can be stored in a computer-readable storage medium that can be read by a computer, and the program can include the processes of the above-mentioned method embodiments when executed. The computer-readable storage medium can be a memory, a disk, an optical disk, etc.

[0122] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A method for extending the single growth time of single crystal diamond, characterized in that: The method for extending the single growth time of single crystal diamond comprises: Obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment for the diamond seed crystal; Obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in stages according to a preset concentration to obtain a second growth reaction environment; According to the second growth reaction environment, a staged temperature increase treatment and a seed crystal single growth treatment are performed to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

2. The method for extending the single growth time of single crystal diamond according to claim 1, characterized in that: The vacuuming and ignition processing of the reaction chamber to obtain the first growth reaction environment of the diamond seed crystal specifically includes: Acquiring a first intra-cavity air pressure range of the reaction cavity, and using a vacuum pump to roughly pump the reaction cavity until the first intra-cavity air pressure range drops to a second intra-cavity air pressure range; Setting a preset flow rate of hydrogen, and charging the preset flow rate of hydrogen into the reaction chamber to perform multiple iterations of cleaning treatment, and completing the vacuum treatment; Turning on a microwave power supply, performing an ignition process on the preset flow rate hydrogen gas filled into the reaction chamber through the microwave power supply, and after the ignition process is completed, setting a first growth reaction environment for the diamond seed crystal; The first growth reaction environment includes a preset hydrogen target flow range, a preset gas pressure range, a preset power range, and a preset crystal surface temperature of the diamond seed crystal.

3. The method for extending the single growth time of single crystal diamond according to claim 1, characterized in that: The preset process gas includes a first process gas, a second process gas, a third process gas and a fourth process gas; The step of obtaining a preset process gas and inputting the preset process gas into the first growth reaction environment in sections according to a preset concentration to obtain a second growth reaction environment specifically includes: Inputting the first process gas of a first preset concentration and the second process gas of a second preset concentration into the first growth reaction environment, and performing a first stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration; Inputting the third process gas of a fifth preset concentration into the first growth reaction environment, and performing a second stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a sixth preset concentration and the second process gas of a seventh preset concentration; Inputting the fourth process gas of the third preset concentration into the first growth reaction environment, and performing a third stage concentration increasing process on the first process gas and the third process gas to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration; The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration constitute a second growth reaction environment.

4. The method for extending the single growth time of single crystal diamond according to claim 3, characterized in that: The step of inputting the first process gas of a first preset concentration and the second process gas of a second preset concentration into the first growth reaction environment, and performing a first-stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of a third preset concentration and the second process gas of a fourth preset concentration specifically includes: Inputting the first process gas of the first preset concentration and the second process gas of the second preset concentration into the first growth reaction environment, and allowing the first process gas of the first preset concentration and the second process gas of the second preset concentration to stay in the first growth reaction environment for a first preset time range; When the residence time reaches the first preset time range, the first preset concentration of the first process gas is increased to the third preset concentration, and the second preset concentration of the second process gas is increased to the fourth preset concentration; The first process gas at the third preset concentration and the second process gas at the fourth preset concentration are kept in the first growth reaction environment for a second preset time range.

5. The method for extending the single growth time of single crystal diamond according to claim 3, characterized in that: The step of inputting the third process gas of the fifth preset concentration into the first growth reaction environment, and performing a second-stage concentration increasing process on the first process gas and the second process gas to obtain the first process gas of the sixth preset concentration and the second process gas of the seventh preset concentration specifically includes: inputting the third process gas of a fifth preset concentration into the first growth reaction environment; increasing the third preset concentration of the first process gas to the sixth preset concentration, and increasing the fourth preset concentration of the second process gas to the seventh preset concentration; The first process gas at the sixth preset concentration, the second process gas at the seventh preset concentration, and the third process gas at the fifth preset concentration are kept in the first growth reaction environment for a third preset time range.

6. The method for extending the single growth time of single crystal diamond according to claim 3, characterized in that: The step of inputting the fourth process gas of the third preset concentration into the first growth reaction environment, and performing a third stage concentration increasing process on the first process gas and the third process gas to obtain the first process gas of the eighth preset concentration and the third process gas of the ninth preset concentration specifically includes: Inputting the fourth process gas of the third preset concentration into the first growth reaction environment; increasing the sixth preset concentration of the first process gas to the eighth preset concentration, and increasing the fifth preset concentration of the third process gas to the ninth preset concentration; The first process gas at the eighth preset concentration, the second process gas at the seventh preset concentration, the third process gas at the ninth preset concentration, and the fourth process gas at the third preset concentration are kept in the first growth reaction environment for a fourth preset time range.

7. The method for extending the single growth time of single crystal diamond according to claim 1, characterized in that: The step of performing a staged temperature increase process and a seed crystal single growth process according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed specifically includes: The temperature of the reaction chamber in the MPCVD device is raised in stages to obtain a second growth reaction environment with different stage temperatures; The diamond seed crystal is subjected to a seed crystal single growth process according to the second growth reaction environment of different stage temperatures to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

8. A system for extending the single growth time of single crystal diamond, characterized in that: The single crystal diamond single growth time extension system comprises: A first growth reaction environment generating module, used for obtaining a diamond seed crystal, placing the diamond seed crystal into a reaction chamber of an MPCVD device, and performing a vacuum treatment and a ignition treatment on the reaction chamber to obtain a first growth reaction environment of the diamond seed crystal; A second growth reaction environment generating module, used for obtaining a preset process gas, and inputting the preset process gas into the first growth reaction environment in sections according to a preset concentration, to obtain a second growth reaction environment; The seed crystal single growth module is used to perform a staged temperature increase process and a seed crystal single growth process according to the second growth reaction environment to obtain a target single crystal diamond after the single growth of the diamond seed crystal is completed.

9. A terminal, characterized in that: The terminal comprises: a memory, a processor, and a single growth time extension program for single crystal diamond stored in the memory and executable on the processor. When the single growth time extension program for single crystal diamond is executed by the processor, the steps of the single growth time extension method for single crystal diamond as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a single crystal diamond single growth time extension program, and when the single crystal diamond single growth time extension program is executed by a processor, the steps of the single crystal diamond single growth time extension method according to any one of claims 1 to 7 are implemented.

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