WO2023051346A1

WO2023051346A1 - Method for manufacturing nitrogen-doped monocrystalline silicon

Info

Publication number: WO2023051346A1
Application number: PCT/CN2022/120211
Authority: WO
Inventors: 徐鹏; 文英熙; 倚娜
Original assignee: 西安奕斯伟材料科技有限公司
Priority date: 2021-09-29
Filing date: 2022-09-21
Publication date: 2023-04-06
Also published as: TW202300716A; CN113846378A

Abstract

A method for manufacturing nitrogen-doped monocrystalline silicon. The method comprises: drawing highly nitrogen-doped monocrystalline silicon by using a silicon nitride crucible and a silicon nitride dopant by means of the Czochralski method; and drawing lightly nitrogen-doped monocrystalline silicon by using a quartz crucible and taking the highly nitrogen-doped monocrystalline silicon as a dopant by means of the Czochralski method.

Description

Method for producing nitrogen-doped single crystal silicon

Cross References to Related Applications

This application claims priority to Chinese Patent Application No. 202111155528.2 filed in China on September 29, 2021, the entire contents of which are hereby incorporated by reference.

technical field

The present application relates to the field of semiconductor silicon wafer production, in particular to a method for manufacturing nitrogen-doped single crystal silicon.

Background technique

With the global development of informatization, semiconductor silicon material is by far the most widely used semiconductor material. Silicon materials account for about 95% of the production and use of semiconductor materials. The size of devices in the application field of silicon wafers continues to decrease. At the same time, the stress on silicon wafers will increase significantly when the integration of devices is gradually increasing. Due to the low mechanical strength of silicon materials, it will affect the setting of processing and manufacturing process parameters. , and silicon wafers are extremely prone to damage and breakage during the product assembly process, resulting in an increase in the production cost of silicon wafers. Therefore, it is of great significance to improve the mechanical strength of silicon wafers.

Silicon wafers used for the production of semiconductor electronic components such as integrated circuits are mainly manufactured by slicing single crystal silicon rods drawn by Czochralski (CZ) method. The Czochralski method involves melting polysilicon in a crucible made of quartz to obtain a silicon melt, immersing a single crystal seed in the silicon melt, and continuously lifting the seed to move away from the surface of the silicon melt, whereby during the movement A single crystal silicon rod grows at the phase interface.

In the above-mentioned production process, it is very advantageous to provide such a silicon wafer: the silicon wafer has a crystal defect-free region (Denuded Zone, DZ) extending from the front side to the body and a denuded zone adjacent to the DZ and further extending to the body. Bulk Micro Defect (BMD) area, where the front side refers to the surface of the silicon wafer that needs to form electronic components. The above-mentioned DZ is important because in order to form electronic components on a silicon wafer, it is required that there are no crystal defects in the formation area of the electronic components, otherwise it will cause failures such as circuit breaks, so that the electronic components are formed in the DZ The influence of crystal defects can be avoided; and the function of the above-mentioned BMD is that it can generate an intrinsic getter (Intrinsic Getter, IG) effect on metal impurities, so that the metal impurities in the silicon wafer can be kept away from the DZ, thereby avoiding the leakage caused by metal impurities Adverse effects such as increased current and decreased film quality of the gate oxide film.

However, in the process of producing the above-mentioned silicon wafers with BMD regions, it is very advantageous to dope the silicon wafers with nitrogen. For example, in the case of silicon doped with nitrogen, it can promote the formation of BMD with nitrogen as the core, so that the BMD can reach a certain density, so that the BMD can effectively function as a metal gettering source, and it can also It has a favorable effect on the density distribution of BMD, such as making the distribution of BMD density more uniform in the radial direction of the silicon wafer, such as making the density of BMD higher in the area near the DZ and gradually decreasing towards the silicon wafer. Doping nitrogen impurities in CZ silicon can also reduce the size of voids (Voids), which can be eliminated by annealing at high temperature. Nitrogen can also improve dislocations and improve the mechanical properties of silicon wafers. In addition, nitrogen impurities are doped in CZ silicon, and nitrogen and oxygen will interact to form nitrogen-oxygen complexes with shallow thermal donor properties, improving the electrical properties of silicon wafers.

In the current process of manufacturing nitrogen-doped single crystal silicon, silicon nitride as a nitrogen dopant and polycrystalline silicon are melted in a quartz crucible. Since the melting temperature of silicon nitride (1800°C) is higher than the melting temperature of polysilicon (1425°C), it is necessary to heat the quartz crucible to a sufficiently high temperature (at least the melting temperature of silicon nitride) and maintain it for a long enough time to obtain nitrogen Doped melt, but when the quartz crucible is heated to such a high temperature and kept for such a long time, the oxygen in the quartz crucible will be excessively precipitated, resulting in an excessively high oxygen content in the melt, and the heating time is reduced to reduce the oxygen concentration. The precipitation will cause the silicon nitride to not be completely melted, and the unmelted particles will enter the ingot and cause dislocations, resulting in the failure of crystal pulling.

Contents of the invention

In order to solve the above technical problems, the embodiment of the present application expects to provide a method for manufacturing nitrogen-doped single crystal silicon, nitrogen atoms can be completely melted into the molten silicon at a relatively low furnace temperature, without affecting the low-nitrogen-doped single crystal silicon. Oxygen concentration in crystalline silicon strengthens the control of oxygen concentration in the preparation of low nitrogen doped single crystal silicon.

The technical scheme of the present application is achieved in this way, including:

Using silicon nitride crucible and silicon nitride dopant to pull high nitrogen doped single crystal silicon by Czochralski method;

Using a quartz crucible and using the high nitrogen doped single crystal silicon as a dopant to pull low nitrogen doped single crystal silicon by Czochralski method.

Optionally, it also includes calculating the quality of the high nitrogen-doped single crystal silicon required for preparing the low nitrogen-doped single crystal silicon.

Optionally, the calculation of the quality of the high nitrogen-doped single crystal silicon required for preparing the low nitrogen-doped single crystal silicon includes:

cutting the highly nitrogen-doped single crystal silicon into high nitrogen-doped ingots with fixed dimensions;

Utilize (Fourier Transform InfRared spectroscopy, FTIR) infrared spectroscopy or (Gas Fusion Analysis, GFA) to measure the nitrogen concentration of a single high nitrogen-doped ingot;

The mass of the high nitrogen doped ingot put into the quartz crucible is determined according to the total nitrogen amount required for preparing the low nitrogen doped single crystal silicon and the nitrogen concentration.

Optionally, said using a silicon nitride crucible and a silicon nitride dopant to pull a highly nitrogen-doped single crystal silicon through the Czochralski method includes:

Putting the silicon nitride dopant into the silicon nitride crucible together with the polysilicon;

Vacuumize the crystal pulling furnace for preparing the highly nitrogen-doped single crystal silicon and pass in protective gas;

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the silicon nitride dopant and the polysilicon are completely melted to obtain a highly nitrogen-doped silicon melt;

High nitrogen-doped single crystal silicon was pulled by Czochralski method.

Optionally, the silicon nitride dopant is particles or powders.

Optionally, no other dopant except the silicon nitride dopant is put into the silicon nitride crucible.

Optionally, using a quartz crucible and using the highly nitrogen-doped single-crystal silicon as a dopant to obtain low-nitrogen-doped single-crystal silicon by Czochralski method includes:

Putting the highly nitrogen-doped monocrystalline silicon and polycrystalline silicon into the quartz crucible;

Vacuumize the crystal pulling furnace for preparing the low-nitrogen-doped single crystal silicon and pass in protective gas;

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the high nitrogen-doped monocrystalline silicon and the polycrystalline silicon are completely melted to obtain a low nitrogen-doped silicon melt;

Low nitrogen-doped single crystal silicon was pulled by Czochralski method.

Optionally, the protective gas is argon.

Description of drawings

Fig. 1 is a schematic diagram of a method for manufacturing nitrogen-doped single crystal silicon according to an embodiment of the present application;

Fig. 2 is a schematic diagram of a method for producing nitrogen-doped single crystal silicon using a silicon nitride crucible and a silicon nitride dopant to pull a highly nitrogen-doped single crystal silicon by the Czochralski method according to an embodiment of the present application ;

3 is a schematic diagram of calculating the quality of the high nitrogen-doped single crystal silicon required to prepare the low nitrogen-doped single crystal silicon in a method for manufacturing nitrogen-doped single crystal silicon according to an embodiment of the present application;

Fig. 4 is a method for producing nitrogen-doped single crystal silicon according to an embodiment of the present application, using a quartz crucible and using the high nitrogen-doped single crystal silicon as a dopant to pull low-nitrogen-doped silicon through the Czochralski method Schematic diagram of single crystal silicon.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly and completely described below.

The silicon single crystal growth method of the present application is based on the Czochralski method, and the silicon single crystal is prepared in a manner of solid-phase nitrogen doping. That is, polysilicon and dopants are placed together in a crucible and heated to form a melt, and the melt is pulled to grow into single crystal silicon. In this application, a silicon nitride crucible and a silicon nitride dopant are used to pull highly nitrogen-doped single crystal silicon through the Czochralski method; Manufacture of low nitrogen doped single crystal silicon. .

When preparing nitrogen-doped single crystal silicon, gas-phase nitrogen doping is often used in this field. After the seed crystal is welded, high-purity nitrogen or nitrogen/argon mixed gas is introduced, and the nitrogen doping concentration of silicon crystal is controlled by the time of nitrogen introduction. Gas-phase nitrogen doping completes nitrogen doping through the reaction of nitrogen and silicon melt, and the purity is high, and the silicon nitride formed by the reaction is less likely to be granulated. However, gas-phase nitrogen doping completely relies on thermal convection for reaction, which is difficult to control in the process Makes the nitrogen doping results less uniform. In addition, the field also uses solid silicon nitride (Si3N4) materials to prepare nitrogen-doped single crystal silicon, so that the nitrogen doping concentration can be precisely controlled. In the process of preparing nitrogen-doped single crystal silicon, it is necessary to heat the polysilicon and silicon nitride dopants in the quartz crucible to a molten state. When the silicon nitride is not completely melted, it will cause dislocation defects in the crystal rod, resulting in Crystal pull failed. However, keeping the furnace temperature at the melting temperature of silicon nitride (about 1900°C) for a long time will cause the softening of the quartz crucible. During the high-temperature production process, the reaction product of molten Si and crucible raw material SiO2 is gaseous SiO. The graphite product placed in the crucible reacts to form CO gas, and CO is easy to enter the silicon melt, introducing carbon and oxygen into the silicon, so that the oxygen content in the silicon melt increases. Excessive oxygen atoms are the main cause of defects. The oxygen precipitation of excessive oxygen atoms in the active region of the device can cause breakdown or leakage. During the annealing process, the generation of oxygen precipitation will reduce the yield of the device. In addition, boron and phosphorus, common impurities in crucible raw materials, will also be transferred to silicon ingots, so that the resistivity of silicon ingots cannot meet the requirements for use. Therefore, in order to avoid the technical problem that melting silicon nitride needs to be heated at high temperature for a long time, the present application finds that the silicon nitride that provides nitrogen atoms is replaced by highly nitrogen-doped single crystal silicon, and the highly nitrogen-doped single crystal silicon that carries nitrogen atoms It can also be completely melted at the melting temperature of silicon (1450°C), which promotes the complete integration of nitrogen into the molten silicon, which solves the technical problems of high furnace temperature and long heating time, and the effect of nitrogen doping is more uniform, and it is easier to achieve the required doping. Nitrogen concentration, simple process, easy to control and low cost.

In this field, the highly nitrogen-doped silicon single crystal required for the above preparation is usually cut from crystal rods manufactured by the suspension zone melting method, but this manufacturing method has high manufacturing cost and low yield. Therefore, this application uses the CZ method to pull high nitrogen-doped single crystal silicon, and then cuts it into high nitrogen-doped ingots with a certain size as a nitrogen source to replace the silicon nitride raw material. However, square or round quartz ceramic crucibles are also used in the process of preparing high-nitrogen-doped single crystal silicon, which has the weakness of softening and devitrification at high temperatures, and is easy to crack and cause high-temperature melt leakage. During the growth of highly nitrogen-doped single crystal silicon in quartz crucibles, the dissolved oxygen is inevitably incorporated into the high nitrogen-doped crystal due to the convection and diffusion of molten silicon and transported to the molten silicon interface or free surface, resulting in high nitrogen-doped crystals. The crystal quality problem, that is to say, will also face the situation that the oxygen concentration in the high nitrogen-doped single crystal silicon increases due to the uncontrollable precipitation of oxygen in the quartz crucible at high temperature for a long time. Moreover, the quartz crucible is a disposable consumable, which cannot be reused and has a very limited service life. At present, the service life of the conventional quartz crucible for Si polycrystalline is less than three days, and the service life of conventional quartz crucible for Si single crystal is about one week. The limit is less than 400 hours, which cannot meet the demand for pulling high nitrogen-doped single crystal silicon. Therefore, in order to obtain highly nitrogen-doped single crystal silicon with high concentration of nitrogen and low concentration of oxygen, the applicant found that using silicon nitride as a crucible material can eliminate the contact between liquid or hot metal silicon and elemental oxygen (assuming that the crucible above The atmosphere is substantially free of oxygen), this feature will cut off the above reaction chain that leads to the introduction of oxygen and carbon contamination in molten silicon, thereby substantially improving the level of oxygen and carbon contamination present in polysilicon, and avoiding uncontrollable oxygen in the quartz crucible The problem of ground precipitation, and the silicon nitride crucible has the advantages of high temperature resistance, low oxygen content, long service life and long-term repeated use, which solves the problem that the quartz crucible cannot meet the requirements of preparing high nitrogen-doped single crystal silicon.

This application is mainly to use a silicon nitride crucible to prepare high nitrogen-doped ingots with high nitrogen content and low oxygen content, and then further use the high nitrogen-doped ingots to prepare low nitrogen-doped single crystal silicon, so as to realize the mechanical strength of silicon wafers Increase, the BMD content inside the monocrystalline silicon increases.

According to a method for manufacturing nitrogen-doped single crystal silicon according to an embodiment of the present application, as shown in FIG. 1 , the method includes the following steps:

Since a silicon nitride crucible is used to melt the silicon nitride dopant, even if it is heated to a very high temperature, excessive oxygen will not be precipitated into the melt as in the related art. The monocrystalline silicon dopant, which has the same melting point as polycrystalline silicon, does not need to heat the quartz crucible to a high temperature for melting silicon nitride as in the related art, thereby reducing oxygen evolution from the quartz crucible.

According to the method for manufacturing nitrogen-doped single crystal silicon according to an embodiment of the present application, as shown in FIG. Silicon includes the following steps.

Put the silicon nitride dopant and polysilicon into the silicon nitride crucible. Select a certain amount of silicon nitride raw material according to the nitrogen concentration required for the high nitrogen-doped single crystal silicon rod that is actually required to be produced. Optionally, the silicon nitride raw material is selected from silicon nitride powder or silicon nitride particles to ensure The quality of high nitrogen-doped ingots. Optionally, only silicon nitride dopants are used when pulling the highly nitrogen-doped single crystal silicon, excluding any other dopants such as boron, phosphorus, arsenic, etc. to avoid affecting the subsequent preparation of low nitrogen-doped single crystal silicon. The crucible is made of silicon nitride crucible prepared by reaction sintering in the related art. Its main raw material is high-purity Si powder or high-purity Si3N4 powder, which is made with sintering additives. The content of Si3N4 in the silicon nitride crucible made by sintering exceeds 82wt%, and the sintered density exceeds 92%, which can fully meet the requirements of the container for pulling silicon single crystal or silicon, and has a long service life and can be reused for a long time. The content of oxygen element is low, and the content of free oxygen atoms is extremely low. Diffusion and introduction of oxygen can be avoided during the crystal pulling process, thereby further controlling the oxygen concentration for subsequent preparation of low nitrogen-doped single crystal silicon.

Vacuumize the crystal pulling furnace for preparing the highly nitrogen-doped single crystal silicon and pass in protective gas. In the crystal pulling process, in order to avoid the oxidation of silicon, it must be carried out under the action of vacuum environment and protective gas. Pass protective gas (high-purity argon) into the crystal pulling furnace, inject it from the top of the furnace, and turn on the vacuum pump at the bottom to pump out the gas, so that the vacuum value in the furnace is kept at a dynamic balance, and the gas flow in the furnace runs through the crystal rod from top to bottom The growth area can immediately take away the silicon oxide and impurity volatiles produced at high temperature. Preferably, the vacuum value in the furnace is kept stable by controlling the intake flow rate and maintaining the vacuum pumping efficiency of the vacuum pump.

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the silicon nitride dopant and the polysilicon are completely melted to obtain a highly nitrogen-doped silicon melt. In this process, first raise the temperature of the furnace chamber to the melting temperature of silicon (about 1450°C to 1550°C) and keep it at this temperature for a period of time to fully dissolve the polysilicon, and then continue to increase the temperature so that the temperature of the furnace chamber exceeds the nitriding temperature. The melting point temperature of the silicon raw material (about 1900° C.) is maintained at this temperature for a period of time until all the silicon nitride raw materials are fully melted, and the nitrogen element is completely integrated into the silicon melt.

High nitrogen-doped single crystal silicon was pulled by Czochralski method. After the silicon raw material is completely melted, the temperature of the furnace chamber is gradually reduced to 1420°C to 1450°C at a cooling rate of 2°C/min to 10°C/min to start pulling the ingot. Since the crucible made of silicon nitride is used, no or very few oxygen atoms are precipitated during the melting process of the silicon nitride raw material, and the high nitrogen-doped single crystal silicon produced has high nitrogen content and low oxygen content.

In order to accurately control the nitrogen-doped concentration in low nitrogen-doped single crystal silicon, it is necessary to control the nitrogen content of high nitrogen-doped single crystal silicon used to prepare low nitrogen-doped single crystal silicon as a nitrogen source, that is, it is necessary to calculate and prepare the low nitrogen-doped single crystal silicon. The quality of the high nitrogen doped single crystal silicon required by nitrogen doped single crystal silicon. In this field, spectral analysis is usually used to identify substances and determine their chemical composition, structure or relative content. At present, the most common spectral analysis technique is to detect chemical bonds in molecules by using Fourier Transform Infrared Spectroscopy (Fourier Transform InfRared spectroscopy, FTIR) to generate infrared absorption spectra of solids, liquids or gases. Samples (such as solids, liquids or gases), measure the transmitted or reflected light intensity for each wavelength, and then qualitatively or quantitatively analyze and determine the type and quantity of substances contained in the sample based on the spectral information. Since such spectral analysis technology can obtain test results without destroying the sample, it is widely used in the content testing of elements or components in the semiconductor industry, especially in the measurement of nitrogen content. Optionally, gas fusion analysis (Gas Fusion Analysis, GFA) method can also be used to measure the nitrogen concentration in the high nitrogen-doped ingot. GFA is a method specially used to quantitatively measure the content of oxygen, carbon or nitrogen in a single crystal silicon sample. For the above purpose, a pulsed electrode furnace is generally used as a heat source, and the sample is melted in a graphite crucible with an inert atmosphere at a high temperature. The compound of the element is reduced and decomposed, and the nitrogen in the sample enters the thermal conductivity cell with the inert gas in the form of nitrogen gas, and the nitrogen is quantitatively detected by the thermal conductivity detection system. It can be seen that, as shown in Figure 3, the calculation of the quality of the high nitrogen-doped single crystal silicon required for the preparation of the low nitrogen-doped single crystal silicon includes the following steps: cutting the made high nitrogen-doped single crystal silicon into a fixed High nitrogen-doped ingots of different sizes; use FTIR infrared spectroscopy to measure the nitrogen concentration content in each high nitrogen-doped ingot; determine the input according to the total nitrogen required for the preparation of the low nitrogen-doped single crystal silicon and the nitrogen concentration The mass of the high nitrogen-doped ingot block into the quartz crucible.

Next, as shown in FIG. 4 , the pulling of low-nitrogen-doped single-crystal silicon by Czochralski method using a quartz crucible and using the high-nitrogen-doped single-crystal silicon as a dopant includes the following steps.

Put the highly nitrogen-doped monocrystalline silicon and polycrystalline silicon into the quartz crucible. Put the polysilicon raw material at the bottom of the quartz crucible, and spread the high nitrogen-doped ingot and other required dopants on the upper layer.

Vacuumize the crystal pulling furnace for preparing the low-nitrogen-doped single crystal silicon and pass in protective gas. In the crystal pulling process, in order to avoid the oxidation of silicon, it must be carried out under the action of vacuum environment and protective gas. Introduce protective gas (high-purity argon) into the single crystal furnace, inject it from the top of the furnace, start the vacuum pump at the bottom to pump out the gas, so that the vacuum value in the furnace is kept at a dynamic balance, and the gas flow in the furnace runs through the ingot from top to bottom The growth area can immediately take away the silicon oxide and impurity volatiles produced at high temperature. Preferably, the vacuum value in the furnace is kept stable by controlling the intake flow rate and maintaining the vacuuming efficiency of the vacuum pump.

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the high nitrogen-doped monocrystalline silicon and the polycrystalline silicon are completely melted to obtain a low nitrogen-doped silicon melt. During this process, the temperature of the furnace chamber is raised to the melting temperature of silicon (about 1450°C to 1550°C) and kept at this temperature for a period of time to fully melt the polysilicon. As a nitrogen source to pull low-nitrogen-doped monocrystalline silicon, the temperature in the furnace does not need to be too high. After a period of time at the melting temperature of polysilicon, the high-nitrogen-doped ingot can be fully melted, so that nitrogen can be fully integrated into the silicon melt. , At this temperature, the quartz crucible does not have problems such as softening and cracking, and the precipitation of elements is within an acceptable range, which will not cause technical problems such as difficult control of oxygen content. And because the high-nitrogen-doped ingot as the nitrogen source uses silicon nitride with high nitrogen content and low oxygen content, it prevents the dopant from bringing excess oxygen to the silicon melt.

Low nitrogen-doped single crystal silicon was pulled by Czochralski method. After the above steps are completed, adjust the temperature of the furnace chamber and slowly put down the seed crystal. The seed crystal in the furnace body undergoes seeding, necking, shouldering, equal-diameter growth, and the final stage to complete the crystal growth process to produce low-nitrogen-doped single crystal silicon. . Optionally, the seed crystal used is single crystal silicon. Further, the quality of the crystal can be adjusted by adjusting parameters such as the rotation speed of the crystal and the rotation speed of the quartz crucible.

According to a method for producing nitrogen-doped single crystal silicon according to the present application, since it utilizes a quartz crucible and uses the high nitrogen-doped single crystal silicon as a dopant to pull low nitrogen-doped single crystal silicon through the Czochralski method, Nitrogen atoms can be fully integrated into the silicon melt at a lower furnace temperature, and the quartz crucible will not precipitate excess oxygen atoms, which improves the control of oxygen concentration and BMD control. In addition, the use of silicon nitride crucible and silicon nitride dopant to pull high nitrogen-doped single crystal silicon through the Czochralski method has the advantages of low cost and high efficiency. The container obtained high nitrogen-doped single crystal silicon with high nitrogen content and low oxygen content, further strengthened the control of oxygen concentration in the subsequent process of pulling low nitrogen-doped single crystal silicon, and reduced the risk of dislocation.

The above is only a specific implementation of the application, but the scope of protection of the application is not limited thereto. Anyone familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the application. Should be covered within the protection scope of this application. Therefore, the protection scope of the present application should be determined by the protection scope of the claims.

Claims

A method for producing nitrogen-doped single crystal silicon, the method comprising:

Using silicon nitride crucible and silicon nitride dopant to pull high nitrogen doped single crystal silicon by Czochralski method;

Using a quartz crucible and using the high nitrogen doped single crystal silicon as a dopant to pull low nitrogen doped single crystal silicon by Czochralski method.
The method for manufacturing nitrogen-doped single crystal silicon according to claim 1, further comprising calculating the quality of the high nitrogen-doped single crystal silicon required for preparing the low nitrogen-doped single crystal silicon.
The method for manufacturing nitrogen-doped single crystal silicon according to claim 2, wherein said calculating the quality of said high nitrogen-doped single crystal silicon required for preparing said low nitrogen-doped single crystal silicon comprises:

cutting the highly nitrogen-doped single crystal silicon into high nitrogen-doped ingots with fixed dimensions;

Utilize FTIR infrared spectroscopy or GFA to measure the nitrogen concentration of a single block of the highly nitrogen-doped ingot;

The mass of the high nitrogen doped ingot put into the quartz crucible is determined according to the total nitrogen amount required for preparing the low nitrogen doped single crystal silicon and the nitrogen concentration.
The method for manufacturing nitrogen-doped single crystal silicon according to claim 1, wherein said using a silicon nitride crucible and a silicon nitride dopant to pull a highly nitrogen-doped single crystal silicon by the Czochralski method comprises:

Putting the silicon nitride dopant into the silicon nitride crucible together with the polysilicon;

Vacuumize the crystal pulling furnace for preparing the highly nitrogen-doped single crystal silicon and pass in protective gas;

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the silicon nitride dopant and the polysilicon are completely melted to obtain a highly nitrogen-doped silicon melt;

High nitrogen-doped single crystal silicon was pulled by Czochralski method.
The method for manufacturing nitrogen-doped single crystal silicon according to claim 4, wherein the silicon nitride dopant is a particle or a powder.
The method for manufacturing nitrogen-doped silicon single crystal according to claim 4, wherein any other dopant other than the silicon nitride dopant is not put into the silicon nitride crucible.
The method for producing nitrogen-doped single crystal silicon according to claim 1, wherein said using a quartz crucible and using said highly nitrogen-doped single crystal silicon as a dopant to obtain low nitrogen-doped silicon through Czochralski method Monocrystalline silicon includes:

Putting the highly nitrogen-doped monocrystalline silicon and polycrystalline silicon into the quartz crucible;

Vacuumize the crystal pulling furnace for preparing the low-nitrogen-doped single crystal silicon and pass in protective gas;

Turn on the heater, increase the temperature of the furnace chamber and keep it warm for a period of time until the high nitrogen-doped monocrystalline silicon and the polycrystalline silicon are completely melted to obtain a low nitrogen-doped silicon melt;

Low nitrogen-doped single crystal silicon was pulled by Czochralski method.
The method for manufacturing nitrogen-doped single crystal silicon according to claim 5 or 7, wherein the protective gas is argon.