reduce <111> Methods for measuring the radial resistivity variation rate of heavily doped single crystals, single crystal rods and their applications

Abstract

The present invention provides a method for reducing <111> Method for radial change rate of resistivity of antimony-doped single crystal in crystal direction and single crystal ingot, involving <111> In the field of crystal orientation single crystal silicon pulling technology, when the crystal ingot enters the equal diameter stage during heavy doping and pulling, the crystal ingot is pulled by adjusting the pulling speed of the crystal ingot within a predetermined equal diameter length. On the one hand, the shape of the solid-liquid interface is improved, so that the deviation of the center resistivity and the edge resistivity is reduced, making the resistivity distribution of the crystal more uniform and improving the uniformity of the electronic properties of the material; on the other hand, the impurity concentration in the (111) atomic close-packed plane and other plane areas is reduced, thereby reducing the <111> The small plane effect of heavily doped single crystals in the crystal direction reduces the radial rate of change (RRG) of resistivity, improves the stability of the electronic properties of the material, and has a wider application.

Description

Technical Field

[0001] The present invention belongs to <111> The technical field of crystal direction single crystal silicon pulling is particularly related to a method for reducing <111> A method for radial change rate of resistivity of heavily doped single crystals in crystal orientation, a single crystal rod and applications. Background Art

[0002] In the field of semiconductor materials, doping is a commonly used technical means to change the electronic properties of materials to achieve specific functions. Among them, crystal growth technology is an important method for preparing single crystal materials, especially semiconductor single crystal materials.

[0003] In the process of crystal growth, the selection of doping materials and the optimization of doping methods are key factors. <111> Due to its crystal orientation characteristics, <111> Atomic arrangement ratio of crystal direction <100> The atoms in the crystal direction are denser and belong to a close-packed plane. Small planes will aggregate and produce a small plane effect, resulting in a higher radial rate of change (RRG) of resistivity, which limits its application areas. Summary of the invention

[0004] In view of this, the present invention provides a method for reducing <111> Method for improving radial change rate of resistivity of heavily doped single crystals in crystal orientation <111> Application range of crystal orientation antimony-doped single crystals.

[0005] It is also necessary to provide a single crystal ingot.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A reduction <111> The method for the radial change rate of the resistivity of a heavily doped single crystal in the crystal direction is to reduce the radial change rate of the resistivity of the heavily doped single crystal in the crystal direction, and when the crystal ingot enters the equal diameter stage, the crystal ingot is pulled by adjusting the pulling speed of the crystal ingot within a predetermined equal diameter length. <111> Radial variation rate of resistivity of heavily doped single crystal in different crystal directions.

[0008] Preferably, the predetermined constant diameter length includes a first predetermined length and a second predetermined length, and drawing is performed at a first predetermined drawing speed within the first predetermined length, and the first predetermined drawing speed is reduced to a second predetermined drawing speed at a predetermined rate within the second predetermined length, and drawing is performed at the second predetermined drawing speed.

[0009] Preferably, the first predetermined length is: 100mm-150mm from the head of the crystal rod to the diameter of the crystal rod.

[0010] Preferably, the second predetermined length is: from the crystal rod having a constant diameter of 100 mm to 150 mm to the end of the crystal rod having a constant diameter.

[0011] Preferably, the first predetermined pulling speed is 0.75 mm / min-0.95 mm / min.

[0012] Preferably, the second predetermined pulling speed is 0.5 mm / min-0.7 mm / min.

[0013] Preferably, the heavily-doped pulled crystal rod is specifically doped with elements such as phosphorus, arsenic, antimony, etc. when pulling the crystal rod.

[0014] Preferably, the predetermined rate is: 0.03mm / min-0.04mm / min.

[0015] A single crystal ingot, by reducing the <111> It is pulled by the method of radial change rate of resistivity of heavily doped single crystal in crystal direction.

[0016] As mentioned above, the single crystal ingot is used as a semiconductor device, optoelectronic device, sensor and detection device, electronic component and integrated circuit device.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention provides a method for reducing <111> The invention discloses a method for calculating the radial change rate of resistivity of a heavily doped single crystal in a crystal direction. When the heavily doped single crystal is pulled into a crystal rod, when the crystal rod enters the equal diameter stage, the pulling speed of the crystal rod is adjusted within a predetermined equal diameter length to pull the crystal rod. On the one hand, the shape of the solid-liquid interface is improved, so that the deviation of the center resistivity and the edge resistivity is reduced, so that the resistivity distribution of the crystal is more uniform, and the uniformity of the electronic properties of the material is improved; on the other hand, the impurity concentration in the (111) atomic close-packed plane and other plane areas is reduced, thereby reducing the impurity concentration in the (111) atomic close-packed plane and other plane areas. <111> The small plane effect of heavily doped single crystals in the crystal direction reduces the radial rate of change (RRG) of resistivity, improves the stability of the electronic properties of the material, and has a wider application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the RRG results of Example 1 and Comparative Example 1.

[0020] Figure 2 Schematic diagram of the RRG results of Example 2 and Comparative Example 2.

[0021] Figure 3 Schematic diagram of the RRG results of Example 3 and Comparative Example 3. DETAILED DESCRIPTION

[0022] The technical solutions and technical effects of the embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings of the present invention.

[0023] A reduction <111> The method for the radial change rate of the resistivity of a heavily doped single crystal in the crystal direction is to reduce the radial change rate of the resistivity of the heavily doped single crystal in the crystal direction, and when the crystal ingot enters the equal diameter stage, the crystal ingot is pulled by adjusting the pulling speed of the crystal ingot within a predetermined equal diameter length. <111> Radial variation rate of resistivity of heavily doped single crystal in different crystal directions.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] The present invention provides a method for reducing <111> The invention discloses a method for calculating the radial change rate of resistivity of a heavily doped single crystal in a crystal direction. When the heavily doped single crystal is pulled into a crystal rod, when the crystal rod enters the equal diameter stage, the pulling speed of the crystal rod is adjusted within a predetermined equal diameter length to pull the crystal rod. On the one hand, the shape of the solid-liquid interface is improved, so that the deviation of the center resistivity and the edge resistivity is reduced, so that the resistivity distribution of the crystal is more uniform, and the uniformity of the electronic properties of the material is improved; on the other hand, the impurity concentration in the (111) atomic close-packed plane and other plane areas is reduced, thereby reducing the impurity concentration in the (111) atomic close-packed plane and other plane areas. <111> The small plane effect of heavily doped single crystals in the crystal direction reduces the radial rate of change of resistivity (RRG) and improves the stability of the electronic properties of the material. It can then be applied in devices to improve the performance and reliability of the devices.

[0026] Furthermore, the predetermined equal diameter length includes a first predetermined length and a second predetermined length, and drawing is performed at a first predetermined drawing speed within the first predetermined length, and the first predetermined drawing speed is reduced to a second predetermined drawing speed at a predetermined rate within the second predetermined length, and drawing is performed at the second predetermined drawing speed.

[0027] Furthermore, the first predetermined length is: from the head of the crystal rod to the diameter of the crystal rod 100mm-150mm.

[0028] Furthermore, the second predetermined length is: from the crystal rod having a uniform diameter of 100 mm to 150 mm to the end of the crystal rod having a uniform diameter.

[0029] Furthermore, the first predetermined pulling speed is 0.75 mm / min-0.95 mm / min.

[0030] Furthermore, the second predetermined pulling speed is 0.5 mm / min-0.7 mm / min.

[0031] Specifically, when the equal-diameter head of the crystal rod is pulled to an equal diameter of 100mm-150mm, pulling is performed at a first predetermined pulling speed to prevent changes in the pulling speed from affecting crystallization. After pulling to an equal diameter of 100mm-150mm, the pulling speed is reduced to a second predetermined pulling speed to keep the solid-liquid interface horizontal and reduce the small plane effect.

[0032] Furthermore, the heavily doped pulled crystal rod specifically comprises doping elements such as phosphorus, arsenic, antimony, etc. when pulling the crystal rod.

[0033] Furthermore, the predetermined rate is: 0.03mm / min-0.04mm / min, to prevent the crystal rod from NG.

[0034] A single crystal ingot, by reducing the <111> It is pulled by the method of radial change rate of resistivity of heavily doped single crystal in crystal direction.

[0035] As mentioned above, the single crystal ingot is used as a semiconductor device, optoelectronic device, sensor and detection device, electronic component and integrated circuit device.

[0036] Specifically, the drawn crystal rod can be used in the manufacture of semiconductor devices. The uniform resistivity distribution can improve the uniformity and stability of the material, thereby improving the performance and reliability of the device. It can also be used in optoelectronic devices, such as photodetectors, fiber optic communication devices, and solar cells. The uniform resistivity distribution can improve the photoelectric conversion efficiency and stability of the device. It can also be used in sensors and detection devices, such as gas sensors, pressure sensors, and temperature sensors. Reducing the radial rate of change (RRG) of resistivity can improve the sensitivity and accuracy of the sensor. It can also be used in electronic components and integrated circuits, such as high-frequency devices, power devices, and radio frequency devices, to improve the performance and reliability of the device.

[0037] Embodiment 1 (arsenic doping):

[0038] Arsenic-doped crystal pulling was performed. When pulling equal diameter, the pulling speed was 0.85 mm / min from the equal diameter head of the crystal rod to the equal diameter of 100 mm. After the equal diameter was 100 mm, the pulling speed was reduced to 0.6 mm / min at a rate of 0.03 mm / min. The pulling speed was maintained at 0.6 mm / min until the equal diameter was completed and the crystal rod was pulled normally. After the crystal pulling process was completed, the arsenic-doped single crystal sample was taken out and the radial distribution test of resistivity and the quality and index test were carried out. The test results are shown as follows Figure 1 As shown in Table 1.

[0039] Embodiment 2 (doped with phosphorus):

[0040] The crystal is pulled by heavy phosphorus doping. When pulling equal diameter, the pulling speed is 0.85mm / min from the equal diameter head of the crystal rod to the equal diameter of 100mm. After the equal diameter is 100, the pulling speed is reduced to 0.6mm / min at a rate of 0.03mm / min, and maintained at 0.6mm / min until the equal diameter is completed. After the crystal rod is pulled, the phosphorus-doped single crystal sample is taken out and the radial distribution test of resistivity and the quality and index test are carried out. The test results are as follows Figure 2 As shown in Table 1.

[0041] Embodiment 3 (antimony doping):

[0042] The crystal is pulled by heavy antimony doping. When pulling equal diameter, the pulling speed is 0.85mm / min from the equal diameter head of the crystal rod to the equal diameter of 100mm. After the equal diameter is 100, the pulling speed is reduced to 0.6mm / min at a rate of 0.03mm / min, and maintained at 0.6mm / min until the equal diameter is completed. After the crystal rod is pulled, the antimony-doped single crystal sample is taken out and the radial distribution test of resistivity and the quality and index test are carried out. The test results are as follows Figure 3 As shown in Table 1.

[0043] Comparative Example 1 (Arsenic-doped):

[0044] Arsenic-doped crystals are pulled. When pulling equal diameters, the pulling speed is 0.85 mm / min from the head of the crystal rod to 100 mm of the crystal rod. After the equal diameter is 100 mm, the pulling speed is maintained at 0.8 mm / min until the equal diameter is completed and the crystal rod is pulled normally. After the crystal pulling process is completed, the arsenic-doped single crystal sample is taken out and the radial distribution test of resistivity and the quality and index test are carried out. The test results are as follows: Figure 1 As shown in Table 1.

[0045] Comparative Example 2 (doped with phosphorus):

[0046] The crystal is pulled by heavy phosphorus doping. When pulling the equal diameter, the pulling speed is 0.85mm / min from the equal diameter head of the crystal rod to the equal diameter of 100mm. After the equal diameter is 100, the pulling speed is maintained at 0.8mm / min until the equal diameter is completed and the crystal rod is pulled normally. After the crystal pulling process is completed, the phosphorus-doped single crystal sample is taken out and the radial distribution test of resistivity and the quality and index test are carried out. The test results are as follows Figure 2 As shown in Table 1.

[0047] Comparative Example 3 (antimony-doped):

[0048] The crystal is pulled by heavy antimony doping. When pulling the equal diameter, the pulling speed is 0.85mm / min from the equal diameter head of the crystal rod to the equal diameter of 100mm. After the equal diameter is 100, the pulling speed is maintained at 0.8mm / min until the equal diameter is completed and the crystal rod is pulled normally. After the crystal pulling process is completed, the antimony-doped single crystal sample is taken out and the radial distribution test of resistivity and the quality and index test are carried out. The test results are as follows Figure 3 As shown in Table 1.

[0049] Table 1

[0050]

[0051] Depend on Figures 1 to 3As shown in Table 1, the RRG level of arsenic doping was basically between 20% and 35% before improvement, and was between 5% and 15% after improvement; the RRG level of phosphorus doping was basically between 15% and 25% before improvement, and was between 5% and 12% after improvement; the RRG level of antimony doping was basically between 20% and 25% before improvement, and was between 10% and 15% after improvement, which can meet the higher requirements for radial resistivity and has a wider range of applications; and as shown in Table 1, the quality of the crystal rod is not affected by adjusting the pulling speed.

[0052] What is disclosed above is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention still fall within the scope of the invention.

Claims

1. A reduction <111> The method for determining the radial change rate of resistivity of a heavily doped single crystal in a crystal orientation is characterized by: When the crystal ingot is pulled by heavy doping, when the crystal ingot enters the equal diameter stage, the crystal ingot is pulled by adjusting the pulling speed within the predetermined equal diameter length to reduce <111> The radial variation rate of resistivity of heavily doped single crystal in crystal orientation; The predetermined constant diameter length includes a first predetermined length and a second predetermined length, and the drawing is performed at a first predetermined drawing speed within the first predetermined length, and the first predetermined drawing speed is reduced to a second predetermined drawing speed at a predetermined rate within the second predetermined length, and the drawing is performed at the second predetermined drawing speed; The first predetermined length is: from the head of the crystal rod to the diameter of the crystal rod 100mm-150mm; The second predetermined length is: from the crystal rod having a uniform diameter of 100 mm to 150 mm to the end of the crystal rod having a uniform diameter; The first predetermined pulling speed is 0.75 mm / min-0.95 mm / min; The second predetermined pulling speed is 0.5 mm / min-0.71 mm / min; The heavily doped pulled crystal rod specifically includes doping elements such as phosphorus, arsenic, antimony, etc. when pulling the crystal rod; The predetermined rate is: 0.03mm / min-0.04mm / min.

2. A single crystal ingot, characterized in that: By reducing the <111> It is pulled by the method of radial change rate of resistivity of heavily doped single crystal in crystal direction.

3. Application of the single crystal ingot as claimed in claim 2 as semiconductor devices, optoelectronic devices, sensors and detection devices, electronic components and integrated circuit devices.

Images