Monocrystalline silicon material and preparation method and application thereof

Abstract

The invention provides a monocrystalline silicon material and a preparation method and application thereof, the monocrystalline silicon material comprises a doping element, the doping element comprises a lithium element, and the mass ratio of the lithium element to the monocrystalline silicon material is (0.01%-0.1%): 1. According to the monocrystalline silicon material provided by the invention, the lithium element is used as a doping element, and the mass ratio of the lithium element to the monocrystalline silicon material is (0.01%-0.1%): 1, so that the purity and conductivity of the monocrystalline silicon material can be improved, and the dislocation density can be reduced, thereby improving the photoelectric conversion performance of the monocrystalline silicon material.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a single crystal silicon material and a preparation method and application thereof. Background Art

[0002] Monocrystalline silicon is the most common type of semiconductor material and is widely used in electronics, optoelectronics, solar energy and other fields. However, the performance of monocrystalline silicon is limited by factors such as impurities and crystal defects. In order to improve the semiconductor performance of monocrystalline silicon, high-purity silicon raw materials are needed to grow crystals and reduce the impurity content as much as possible. However, absolutely pure materials do not exist in industry. For example, the metal impurity content of monocrystalline silicon raw materials produced by the modified Siemens process, which is widely used in the photovoltaic field, is generally 5×10 15 cm -3 ; However, the oxygen, carbon, metal and other impurities in photovoltaic silicon raw materials produced by some low-cost methods are often as high as 5×10 16 cm -3 Therefore, for silicon raw materials with a certain purity, how to improve the performance of single crystal silicon is more important.

[0003] In the prior art, single crystal silicon materials still have problems of low purity, poor conductivity and high dislocation density. Summary of the invention

[0004] The main purpose of the present invention is to provide a single crystal silicon material, which has higher purity, lower dislocation density and excellent conductivity.

[0005] The present invention also provides a method for preparing a single crystal silicon material, which can prepare the above-mentioned single crystal silicon material, and has a simple process and low cost.

[0006] The present invention also provides a semiconductor element, comprising the above-mentioned single crystal silicon material, so that the semiconductor element has excellent photoelectric conversion efficiency and stability.

[0007] In a first aspect, the present invention provides a single crystal silicon material, wherein the single crystal silicon material includes a doping element, wherein the doping element includes a lithium element, and the mass ratio of the lithium element to the single crystal silicon material is (0.01%-0.1%):1.

[0008] As mentioned above, the mass ratio of the lithium element to the single crystal silicon material is (0.05%-0.1%):1.

[0009] The single crystal silicon material as described above, wherein the dislocation density of the single crystal silicon material is 0.1×10 4 cm -2 -1.4×10 4 cm -2 .

[0010] The single crystal silicon material as described above, wherein the resistivity of the single crystal silicon material is 0.6Ω·cm-0.9Ω·cm;

[0011] And / or, the carrier mobility of the single crystal silicon material is 1700cm 2 / (V·s)-2100cm 2 / (V·s).

[0012] The single crystal silicon material as described above has a purity greater than or equal to 99.999%.

[0013] In a second aspect, the present invention provides a method for preparing the single crystal silicon material as described above, comprising the following steps:

[0014] 1) using a lithium source to perform lithium doping treatment on a raw material for forming single crystal silicon to obtain a doped intermediate;

[0015] 2) Annealing the doped intermediate to obtain the single crystal silicon material.

[0016] In the preparation method as described above, the purity of the raw material used to form single crystal silicon is greater than or equal to 99.999%.

[0017] In the preparation method as described above, the process of using a lithium source to perform lithium doping treatment on the raw material for forming single crystal silicon comprises: using a lithium source solution to perform the lithium doping treatment on the raw material for forming single crystal silicon to obtain the doped intermediate;

[0018] Wherein, the mass fraction of lithium element in the lithium source solution is 0.001%-0.01%;

[0019] And / or, the mass ratio of the lithium element in the lithium source to the raw material for forming single crystal silicon is (0.01%-0.1%):1.

[0020] According to the preparation method described above, the temperature of the lithium doping treatment is 1421° C.-1462° C., the time of the lithium doping treatment is 5 min-15 min, and the pressure of the lithium doping treatment is 7 torr-9 torr;

[0021] And / or, the temperature of the annealing treatment is 1100° C.-1300° C., and the time of the annealing treatment is 3 h-5 h.

[0022] In a third aspect, the present invention provides a semiconductor element, wherein the semiconductor element comprises the single crystal silicon material as described above or the single crystal silicon material prepared by the preparation method as described above.

[0023] The single crystal silicon material provided by the present invention uses lithium as a doping element, and the mass ratio of lithium to single crystal silicon material is (0.01%-0.1%):1, which can improve the purity and conductivity of the single crystal silicon material and reduce the dislocation density, thereby improving the photoelectric conversion performance of the single crystal silicon material. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] In a first aspect, the present invention provides a single crystal silicon material, which includes a doping element, wherein the doping element includes a lithium element, and the mass ratio of the lithium element to the single crystal silicon material is (0.01%-0.1%):1, for example, it can be 0.01%:1, 0.03%:1, 0.05%:1, 0.07%:1, 0.1%:1 or a range consisting of any two of them.

[0026] First of all, it should be noted that purity refers to the percentage of the mass of silicon in the single crystal silicon material to the total mass of the entire material, which is the mass of silicon divided by the total mass of the single crystal silicon material. Dislocation density is the sum of the lengths of dislocation lines per unit volume or unit area. It is a physical quantity that describes the number of dislocations in a material and is usually used to evaluate the structural integrity and degree of defects in crystalline materials.

[0027] The single crystal silicon material in the present invention includes the doping element lithium, and the mass ratio of lithium to the single crystal silicon material is (0.01%-0.1%): 1, which can improve the purity and conductivity of the single crystal silicon material, reduce the dislocation density, and thus significantly improve the crystal quality and service life of the single crystal silicon material. It is speculated that this may be because the lithium element, as a dopant, can effectively capture and neutralize the impurity atoms and defects in the single crystal silicon material. This is because lithium atoms have high chemical activity and can form stable compounds with impurity atoms, thereby reducing the influence of impurities on the purity of the material, reducing the formation of oxides and sulfides on the surface of the single crystal silicon material, enhancing the compactness of the oxide film on the surface of the single crystal silicon material, and improving the surface symmetry of the single crystal silicon material, thereby improving its optical properties. The lithium element has a regulating effect on the impurity concentration in the single crystal silicon material, so that it has a more consistent chemical composition, which helps to improve the photoelectric properties of the single crystal silicon material and improve its photoelectric conversion efficiency and stability. In addition, the lithium element can fill the conductive channel in the single crystal silicon crystal, reduce the scattering of electrons, and reduce the resistivity, thereby improving the conductive properties of the single crystal silicon. This helps to improve the working efficiency and stability of semiconductor devices. As an n-type dopant, lithium can provide additional free electrons or holes to change the resistivity of the material; it can also change the energy band structure of single-crystal silicon and reduce the mobility of electrons, thereby improving the conductivity of the material. On the other hand, lithium doping can change the stress distribution of the single-crystal silicon lattice, reduce the stress concentration of the lattice, and thus reduce the formation and expansion of dislocations. The distribution of lithium atoms in the single-crystal silicon lattice can pin the dislocation line and hinder the movement of dislocations, thereby reducing the dislocation density, thereby improving its superconductivity and contributing to the development of new superconducting materials and devices.

[0028] When lithium is added to the single crystal silicon material, a new solid solution will be formed, and this solid solution has better conductivity and lower dislocation density, thereby improving the purity and conductivity of the single crystal silicon material, reducing the dislocation density, and reducing the defects of the single crystal silicon material, thereby improving the life and performance of the single crystal silicon material. At the same time, the single crystal silicon material doped with lithium also has better mechanical properties and better corrosion resistance.

[0029] The single crystal silicon material provided by the present invention uses lithium as a doping element, and the mass ratio of lithium to single crystal silicon material is (0.01%-0.1%):1, which can improve the purity and conductivity of the single crystal silicon material and reduce the dislocation density, thereby significantly improving the photoelectric conversion performance of the single crystal silicon material.

[0030] In some embodiments of the present invention, the mass ratio of the lithium element to the single crystal silicon material is (0.05%-0.1%):1, for example, it can be 0.05%:1, 0.06%:1, 0.07%:1, 0.08%:1, 0.09%:1, 0.1%:1 or a range consisting of any two of them. Within this concentration range, the lithium element can maximize its role in improving the electrical conductivity while avoiding adverse effects on the crystal structure of the single crystal silicon, further improving the purity and electrical conductivity of the single crystal silicon material and reducing the dislocation density.

[0031] In some embodiments of the present invention, the dislocation density of the single crystal silicon material is 0.1×10 4 cm -2 -1.4×10 4 cm -2 , for example, it can be 0.1×10 4 cm -2 , 0.3×10 4 cm -2 , 0.5×10 4 cm -2 , 0.8×10 4 cm -2 , 1.0×10 4 cm -2 , 1.4×10 4 cm -2 Or a range consisting of any two of them.

[0032] The dislocation density of the monocrystalline silicon material in the present invention is within the above range, which means that the lattice defects are reduced, and the leakage current caused by the defects is reduced, thereby improving the electrical performance and reliability of the device. Dislocations and other lattice defects can serve as recombination centers for carriers, reducing the life of photogenerated carriers. A lower dislocation density reduces these recombination centers, thereby improving the photoelectric conversion efficiency. A higher photoelectric conversion efficiency means that under the same lighting conditions, solar energy can generate more current and improve the overall output power. In addition, dislocations are stress concentration points in the material, and a low dislocation density means that the stress distribution is more uniform, thereby improving the mechanical strength and fracture resistance of the material and extending the service life of the device. On the other hand, materials with a low dislocation density have better thermal conductivity, can dissipate heat more effectively, and reduce the performance degradation or damage of the device caused by overheating during operation.

[0033] In some embodiments of the present invention, the resistivity of the single crystal silicon material is 0.6Ω·cm-0.9Ω·cm.

[0034] In some embodiments, the carrier mobility of the single crystal silicon material is 1700 cm 2 / (V

[0035] s)-2100cm 2 / (V·s).

[0036] For example, the resistivity of the single crystal silicon material may be 0.6 Ω·cm, 0.7 Ω·cm, 0.75 Ω·cm, 0.8 Ω·cm, 0.9 Ω·cm, or any two thereof. The carrier mobility of the single crystal silicon material may be 1700 cm 2 / (V·s), 1800cm 2 / (V·s), 1900cm 2 / (V·s), 2000cm 2 / (V·s), 2100cm 2 / (V·s) or a range consisting of any two of them.

[0037] The resistivity and carrier mobility of the single crystal silicon material in the present invention are within the above ranges, which can improve the conductivity of the single crystal silicon material, so that electrons and holes move faster under the action of the electric field, thereby improving the switching speed of the electronic device, allowing the device to operate at a higher frequency, and being suitable for high-frequency communication and high-speed data processing applications. It can also reduce the recombination loss of carriers, increase the life of photogenerated carriers, and thus improve the photoelectric conversion efficiency of solar cells. It can also reduce the on-resistance of power semiconductor devices, thereby reducing power loss and improving efficiency.

[0038] In some embodiments of the present invention, the purity of the single crystal silicon material is greater than or equal to 99.999%, for example, it can be 99.9991%, 99.9992%, 99.9994%, 99.9995%, 99.9998% or a range consisting of any two thereof.

[0039] The purity of the single crystal silicon material in the present invention is greater than or equal to 99.999%, and the impurity content is low, which reduces the recombination center of the carrier, thereby increasing the life of the photogenerated carrier, and helping to improve the photoelectric conversion efficiency of the solar cell. In addition, the high-purity single crystal silicon material has fewer impurities and defects, high electron mobility, reduced leakage current, and improved electrical performance and reliability of the device. The high-purity single crystal silicon material has fewer impurities and defects, and can also reduce stress concentration points, thereby improving the mechanical strength and fracture resistance of the material.

[0040] In a second aspect, the present invention provides a method for preparing the single crystal silicon material as described above, comprising the following steps:

[0041] 1) using a lithium source to perform lithium doping treatment on a raw material for forming single crystal silicon to obtain a doped intermediate;

[0042] 2) Annealing the doped intermediate to obtain the single crystal silicon material.

[0043] In step 1) of the present invention, the lithium source can be single substance lithium or a lithium-containing compound, and the lithium-containing compound includes at least one of lithium hydroxide, lithium chloride, lithium nitrate, lithium carbonate or lithium fluoride. Select a suitable single substance lithium or lithium-containing compound as the lithium source, and prepare it into a lithium source solution or powder suitable for doping. The raw material for forming single crystal silicon, for example, polycrystalline silicon, is placed in a doping device, and the lithium element is uniformly doped into the raw material for forming single crystal silicon by gas phase doping (for example, vapor deposition), solid phase doping or liquid phase doping (for example, ion implantation) and other methods to obtain a doped intermediate. During the doping process, the temperature, time, pressure and concentration of lithium in the lithium source of the lithium element doping treatment are controlled to ensure the uniform distribution and stable existence of the lithium element in the raw material for forming single crystal silicon.

[0044] 2) Annealing the doped intermediate to eliminate stress generated during the doping process, improve the crystal quality and performance of the single crystal silicon material, and obtain a single crystal silicon material. Specifically, the doped intermediate can be placed in a vacuum or inert gas atmosphere for annealing to stabilize the distribution of lithium elements in the single crystal silicon and eliminate some lattice defects.

[0045] The method for preparing single crystal silicon of the present invention can prepare the single crystal silicon material of the first aspect mentioned above, and the single crystal silicon material has high purity, low dislocation density and excellent conductivity, thereby significantly improving the photoelectric conversion performance of the single crystal silicon material.

[0046] In some embodiments of the present invention, the purity of the raw material used to form single crystal silicon is greater than or equal to 99.999%, for example, it can be 99.9991%, 99.9992%, 99.9994%, 99.9995%, 99.9998% or a range consisting of any two of them.

[0047] The purity of the raw materials used to form single crystal silicon in the present invention is greater than or equal to 99.999%, which is conducive to the preparation of single crystal silicon materials with higher purity, thereby helping to improve the photoelectric conversion efficiency of solar cells, improve the electrical performance and reliability of the device, and also improve the mechanical strength and fracture resistance of the material, thereby extending the service life of the device.

[0048] In some embodiments of the present invention, the process of using a lithium source to perform lithium doping treatment on the raw material for forming single crystal silicon includes: using a lithium source solution to perform the lithium doping treatment on the raw material for forming single crystal silicon to obtain the doped intermediate; wherein the mass fraction of the lithium element in the lithium source solution is 0.001%-0.01%.

[0049] In some embodiments, the mass ratio of the lithium element in the lithium source to the raw material for forming single crystal silicon is (0.01%-0.1%): 1. Those skilled in the art can calculate the amount of the lithium source solution based on the actual mass fraction of the lithium element in the lithium source solution to ensure that the mass ratio of the lithium element to the raw material for forming single crystal silicon is (0.01%-0.1%): 1.

[0050] Exemplarily, the mass fraction of lithium in the lithium source solution may be 0.001%, 0.002%, 0.004%, 0.005%, 0.007%, 0.009%, 0.01% or any two thereof. The mass ratio of lithium in the lithium source to the raw material for forming single crystal silicon may be 0.01%:1, 0.02%:1, 0.03%:1, 0.04%:1, 0.05%:1, 0.06%:1, 0.07%:1, 0.08%:1, 0.09%:1, 0.1%:1 or any two thereof.

[0051] In the present invention, a lithium source solution is used to perform lithium doping treatment on raw materials for forming single crystal silicon. Specifically, the lithium source can be prepared into a lithium source solution, wherein the mass fraction of lithium in the lithium source solution is 0.001%-0.01%. The raw materials for forming single crystal silicon are placed in a gas phase doping device, and the lithium source solution is sprayed into the gas phase doping device at a constant flow rate, so that the lithium element is uniformly doped into the raw materials for forming single crystal silicon. Among them, the mass ratio of lithium in the lithium source and the raw materials for forming single crystal silicon is (0.01%-0.1%):1, which is conducive to obtaining a lithium doping amount of 0.01%-0.1% in the final single crystal silicon material. The mass fraction of lithium in the lithium source solution is within the above range, which can improve the uniformity of lithium doping, thereby improving the purity and conductivity of the single crystal silicon material and reducing the dislocation density.

[0052] In some embodiments of the present invention, the temperature of the lithium doping treatment is 1421° C.-1462° C., the time of the lithium doping treatment is 5 min-15 min, and the pressure of the lithium doping treatment is 7 Torr-9 Torr.

[0053] In some embodiments, the annealing treatment is performed at a temperature of 1100° C.-1300° C., and the annealing treatment time is 3 h-5 h.

[0054] Exemplarily, the temperature of the lithium doping treatment may be 1421°C, 1425°C, 1430°C, 1440°C, 1455°C, 1458°C, 1462°C, or a range consisting of any two thereof. The time of the lithium doping treatment may be 5 min, 7 min, 10 min, 12 min, 15 min, or a range consisting of any two thereof. The pressure of the lithium doping treatment may be 7 Torr, 7.5 Torr, 8 Torr, 8.5 Torr, 9 Torr, or a range consisting of any two thereof. The temperature of the annealing treatment may be 1100°C, 1150°C, 1200°C, 1250°C, 1300°C, or a range consisting of any two thereof. The time of the annealing treatment may be 3 h, 3.5 h, 4 h, 4.5 h, 5 h, or a range consisting of any two thereof.

[0055] The temperature, time and pressure of the lithium element doping treatment in the present invention are within the above ranges, which can further allow the lithium element to be uniformly and stably doped into the raw material for forming single crystal silicon.

[0056] The temperature and time of the annealing treatment in the present invention are within the above ranges, which can further eliminate the stress generated during the doping process, stabilize the distribution of lithium elements in the single crystal silicon and eliminate some lattice defects, thereby improving the crystallization quality and performance of the single crystal silicon material.

[0057] In a third aspect, the present invention provides a semiconductor element, wherein the semiconductor element comprises the single crystal silicon material as described above or the single crystal silicon material prepared by the preparation method as described above.

[0058] The semiconductor element of the present invention may be a conventional semiconductor element in the art, such as a solar cell. Since the semiconductor element includes the above-mentioned single crystal silicon material, the semiconductor element has excellent photoelectric conversion efficiency and stability.

[0059] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0060] Example 1

[0061] The method for preparing the single crystal silicon material of this embodiment comprises the following steps:

[0062] 1) Select polysilicon with a purity of 99.999% as the raw material for forming single crystal silicon, and prepare single lithium into a lithium source solution with a mass fraction of 0.01%. The mass ratio of lithium element in the lithium source to the raw material for forming single crystal silicon is 0.05%:1, which is recorded as ratio 1.

[0063] 2) placing the raw material for forming single crystal silicon in a vapor phase doping device, setting the doping treatment temperature to 1458° C., the doping time to 10 min, and the doping pressure to 8 Torr, spraying the lithium source solution into the vapor phase doping device at a constant flow rate to obtain a doped intermediate.

[0064] 3) The doped intermediate was annealed at a temperature of 1200° C. for 4 hours to obtain a single crystal silicon material. The performance of the single crystal silicon material was tested, and the results are shown in Table 1.

[0065] Example 2

[0066] The preparation methods of the single crystal silicon material in Example 2 and Example 1 are basically the same, except that the single substance lithium is prepared into a lithium source solution with a mass fraction of 0.001%.

[0067] Example 3

[0068] The preparation method of the single crystal silicon material in Example 3 is basically the same as that in Example 1, except that the mass ratio of the lithium element in the lithium source to the raw material for forming the single crystal silicon is 0.01%:1.

[0069] Example 4

[0070] The preparation method of the single crystal silicon material of Example 4 is basically the same as that of Example 1, except that the mass ratio of the lithium element in the lithium source to the raw material for forming single crystal silicon is 0.1%:1, the doping treatment temperature is set to 1421°C, the doping time is 15 minutes, and the doping pressure is 7 Torr.

[0071] Example 5

[0072] The preparation method of the single crystal silicon material in Example 5 is basically the same as that in Example 4, except that the temperature of the doping treatment is set to 1462° C., the doping time is set to 5 min, and the doping pressure is set to 9 Torr.

[0073] Example 6

[0074] The preparation method of the single crystal silicon material of Example 6 is basically the same as that of Example 1, except that the temperature of the doping treatment is 1450° C., the temperature of the annealing treatment is 1300° C., and the annealing time is 3 hours.

[0075] Example 7

[0076] The preparation method of the single crystal silicon material of Example 7 is basically the same as that of Example 1, except that the temperature of the doping treatment is 1450°C, the mass ratio of the lithium element in the lithium source to the raw material for forming single crystal silicon is 0.1%:1, the temperature of the annealing treatment is 1100°C, and the annealing time is 5h.

[0077] Comparative Example 1

[0078] The preparation methods of the single crystal silicon materials of Comparative Example 1 and Example 1 are basically the same, except that the temperature of the doping treatment is 1450° C., and the mass ratio of the lithium element in the lithium source to the raw material for forming the single crystal silicon is 0.005%:1.

[0079] Comparative Example 2

[0080] The preparation methods of the single crystal silicon material in Comparative Example 2 and Example 1 are basically the same, except that lithium doping is not performed.

[0081] Comparative Example 3

[0082] The preparation method of the single crystal silicon material in Comparative Example 3 is substantially the same as that in Example 1, except that the mass ratio of the lithium element in the lithium source to the raw material for forming the single crystal silicon is 0.15%:1.

[0083] Test example

[0084] 1. Mass ratio of lithium element to single crystal silicon material: firstly, a quantitative amount of single crystal silicon material is extracted from each embodiment and comparative example, then lithium element is dissolved from the single crystal silicon material, and then the lithium content is determined by inductively coupled plasma mass spectrometry or atomic absorption spectrometry, and finally the mass ratio of lithium element to single crystal silicon material is calculated.

[0085] 2. Purity of single crystal silicon material: The purity of the single crystal silicon material of each embodiment and comparative example was measured by Fourier transform infrared spectroscopy.

[0086] 3. Resistivity: The single crystal silicon material of each embodiment and comparative example was prepared into a single crystal silicon wafer, and the resistivity of the single crystal silicon material of each embodiment and comparative example was tested using an FT-341 four-probe tester.

[0087] 4. Carrier mobility: The single crystal silicon material of each embodiment and comparative example was prepared into a single crystal silicon wafer, and the carrier mobility was measured by using the Hall effect measurement method.

[0088] 5. Dislocation density: The single crystal silicon materials of each embodiment and comparative example were prepared into single crystal silicon wafers, and the dislocation density was measured by X-ray diffraction method.

[0089] Table 1

[0090]

[0091]

[0092] It can be seen from Table 1 that, compared with the comparative example, the single crystal silicon material provided by the present invention uses lithium as a doping element, and the mass ratio of lithium to single crystal silicon material is (0.01%-0.1%):1, which can improve the purity and conductivity of the single crystal silicon material, reduce the dislocation density, and thus significantly improve the photoelectric conversion performance of the single crystal silicon material.

[0093] From the comparison between Example 1 and Comparative Examples 1-3, it can be seen that the single crystal silicon material provided by the present invention has higher purity, lower dislocation density and excellent conductivity, thereby significantly improving the photoelectric conversion performance of the single crystal silicon material.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A single crystal silicon material, characterized in that: The single crystal silicon material includes doping elements, the doping elements include lithium elements, and the mass ratio of the lithium element to the single crystal silicon material is (0.01%-0.1%):

1.

2. The single crystal silicon material according to claim 1, characterized in that: The mass ratio of the lithium element to the single crystal silicon material is (0.05%-0.1%):

1.

3. The single crystal silicon material according to claim 1 or 2, characterized in that: The dislocation density of the single crystal silicon material is 0.1×10 4 cm -2 -1.4×10 4 cm -2 .

4. The single crystal silicon material according to any one of claims 1 to 3, characterized in that: The resistivity of the single crystal silicon material is 0.6Ω·cm-0.9Ω·cm; And / or, the carrier mobility of the single crystal silicon material is 1700cm 2 / (V·s)-2100cm 2 / (V·s).

5. The single crystal silicon material according to any one of claims 1 to 4, characterized in that: The purity of the single crystal silicon material is greater than or equal to 99.999%.

6. A method for preparing a single crystal silicon material according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) using a lithium source to perform lithium doping treatment on a raw material for forming single crystal silicon to obtain a doped intermediate; 2) Annealing the doped intermediate to obtain the single crystal silicon material.

7. The preparation method according to claim 6, characterized in that: The purity of the raw material used to form single crystal silicon is greater than or equal to 99.999%.

8. The preparation method according to claim 6 or 7, characterized in that: The process of using a lithium source to perform lithium doping treatment on the raw material for forming single crystal silicon includes: using a lithium source solution to perform the lithium doping treatment on the raw material for forming single crystal silicon to obtain the doped intermediate; Wherein, the mass fraction of lithium element in the lithium source solution is 0.001%-0.01%; And / or, the mass ratio of the lithium element in the lithium source to the raw material for forming single crystal silicon is (0.01%-0.1%):

1.

9. The preparation method according to any one of claims 6 to 8, characterized in that: The temperature of the lithium doping treatment is 1421° C.-1462° C., the time of the lithium doping treatment is 5 min-15 min, and the pressure of the lithium doping treatment is 7 torr-9 torr; And / or, the temperature of the annealing treatment is 1100° C.-1300° C., and the time of the annealing treatment is 3 h-5 h.

10. A semiconductor element, characterized in that: The semiconductor element comprises the single crystal silicon material according to any one of claims 1 to 5 or the single crystal silicon material prepared by the preparation method according to any one of claims 6 to 9.

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