阅读说明：本技术 超高纯锗单晶籽晶的制备方法 (Method for preparing ultra-high pure germanium single crystal seed crystal ) 是由 顾小英 狄聚青 赵青松 牛晓东 于 2021-09-08 设计创作，主要内容包括：本公开提供一种超高纯锗单晶籽晶的制备方法,其包括步骤：步骤一,将单晶锗去头去尾取中间得到圆柱体,圆柱体纯度和位错较好的一头标为尾部,差的标为头部；步骤二,圆柱体和砧板一起放入切割机里；步骤三,设置切割程序,对圆柱体切割；步骤四,旋转圆柱体,重复步骤三中切割程序,得到长方条；步骤五,将长方条放入滚磨机中,滚磨后得到籽晶；步骤六,将步骤五中的籽晶腐蚀,高纯氮气吹干；步骤七,用步骤六中籽晶,提拉多晶锗料,提拉出单晶锗；然后再后面的操作中重复步骤一～步骤六进行两次提拉过程,得到超高纯锗单晶籽晶。(The invention provides a preparation method of ultra-high pure germanium single crystal seed crystals, which comprises the following steps: firstly, removing heads, tails and middle parts of single crystal germanium to obtain a cylinder, wherein a head mark with better purity and dislocation of the cylinder is a tail part, and a head mark with poor purity and dislocation is a head part; secondly, putting the cylinder and the chopping block into a cutting machine; setting a cutting program, and cutting the cylinder; rotating the cylinder, and repeating the cutting procedure in the third step to obtain rectangular strips; putting the rectangular bar into a tumbling mill, and obtaining seed crystals after tumbling; step six, corroding the seed crystals in the step five, and drying the seed crystals by using high-purity nitrogen; step seven, using the seed crystal in the step six to pull the polycrystalline germanium material and pull out single crystal germanium; then, in the following operation, the first step to the sixth step are repeated to carry out the twice pulling process, and the ultra-high pure germanium single crystal seed crystal is obtained.)

1. A preparation method of ultra-high purity germanium single crystal seed crystals is characterized by comprising the following steps:

firstly, removing heads and tails of single crystal germanium, taking the middle of the single crystal germanium to obtain a cylinder, and detecting the purity and dislocation of two ends of the cylinder, wherein the head label with better purity and dislocation is a tail part, and the head label with poorer purity and dislocation is a head part;

fixing any one end of the cylinder on a cutting board, and putting the fixed cylinder and the cutting board into a cutting machine;

setting a cutting program for the cutting machine, and cutting the cylinder;

rotating the cylinder, and repeating the cutting procedure in the third step to obtain rectangular strips;

putting the rectangular bar into a tumbling mill, setting a tumbling procedure, and obtaining seed crystals after tumbling;

step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen;

step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the purity higher than that of the single crystal germanium in the step one, and pulling out the single crystal germanium;

step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals;

step nine, using the single crystal seed crystal obtained in the step eight to pull the ultra-high purity polycrystalline germanium material with the purity higher than that of the step seven, and pulling out single crystal germanium;

step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals;

step eleven, using the single crystal seed crystal obtained in the step ten to pull the ultra-high purity polycrystalline germanium material with the purity higher than that in the step nine, and pulling out single crystal germanium;

and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high purity germanium single crystal seed crystal.

2. The method for preparing ultra-high purity germanium single crystal seed crystals as claimed in claim 1, wherein the size of the single crystal germanium used in the first step is 2-4 inches.

3. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 1, wherein the length of the cylinder obtained in the first step is 110mm to 120 mm.

4. The method for preparing the ultra-high pure germanium single crystal seed crystal according to claim 1, wherein the thickness of the chopping block in the second step is 2cm to 5 cm.

5. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 1,

in the third step, the cutting procedure is to cut the cutting line along the longitudinal direction of the cylinder, and the cutting line is set to move from 111 mm-121 mm to 0mm along the z axis at the speed of 4 mm/min-6 mm/min; then moving the workpiece from 0mm to 111 mm-121 mm at a speed of 50 mm/min-60 mm/min, and then moving the workpiece along the x axis at a speed of 50 mm/min-60 mm/min; repeating for 2-6 times.

6. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 5, wherein the diameter of the cutting line is 0.4mm to 0.6 mm.

7. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 1, wherein in step four, the rotation angle of the cylinder is 90 ° or 270 °.

8. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 1, wherein in step four, the size of the rectangular bar is 15 x 110mm to 120mm³Cross section of 15X 15mm²。

9. The method for preparing an ultra-high purity germanium single crystal seed crystal as claimed in claim 1, wherein the tumbling procedure in step five is to roll the rectangular strip into a cylinder with a diameter of 11.8 mm-12.2 mm, then roll the strip from 0 mm-20 mm from the head into a truncated cone with an angle of 4 °, and finally roll the strip from 20 mm-110 mm and 121mm into a cylinder with a diameter of 9.0 mm-9.4 mm.

10. The method for preparing an ultra-high purity germanium single crystal seed crystal according to claim 1, wherein in step six, the nitrogen gas is used at a concentration of 9N.

Technical Field

The invention relates to the field of preparation of ultra-high pure germanium single crystals, in particular to a preparation method of ultra-high pure germanium single crystal seed crystals.

Background

The existing method for preparing the ultra-high purity germanium single crystal pulling seed crystal is a full-manual or semi-manual and semi-mechanical method, and the prepared seed crystal is too coarse, the coaxiality is not good enough, and the purity of the seed crystal is not high enough. The ultrahigh germanium single crystal seed crystal with the carrier concentration of E10 is not sold at home, is difficult to buy abroad and is expensive, and the price of the ultrahigh germanium single crystal seed crystal with the carrier concentration of E10 is about 20 times that of the ultrahigh germanium single crystal seed crystal with the carrier concentration of E12, so that a method for preparing the ultrahigh pure germanium single crystal seed crystal needs to be researched.

Disclosure of Invention

In view of the problems in the background art, it is an object of the present disclosure to provide a method for preparing an ultra-high purity germanium single crystal seed.

In order to achieve the above object, the present disclosure provides a method for preparing an ultra-high purity germanium single crystal seed crystal, comprising the steps of: firstly, removing heads and tails of single crystal germanium, taking the middle of the single crystal germanium to obtain a cylinder, and detecting the purity and dislocation of two ends of the cylinder, wherein the head label with better purity and dislocation is a tail part, and the head label with poorer purity and dislocation is a head part; fixing any one end of the cylinder on a cutting board, and putting the fixed cylinder and the cutting board into a cutting machine; setting a cutting program for the cutting machine, and cutting the cylinder; rotating the cylinder, and repeating the cutting procedure in the third step to obtain rectangular strips; putting the rectangular bar into a tumbling mill, setting a tumbling procedure, and obtaining seed crystals after tumbling; step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen; step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the purity higher than that of the single crystal germanium in the step one, and pulling out the single crystal germanium; step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals; step nine, using the single crystal seed crystal obtained in the step eight to pull the ultra-high purity polycrystalline germanium material with the purity higher than that of the step seven, and pulling out single crystal germanium; step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals; step eleven, using the single crystal seed crystal obtained in the step ten to pull the ultra-high purity polycrystalline germanium material with the purity higher than that in the step nine, and pulling out single crystal germanium; and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high purity germanium single crystal seed crystal.

In some embodiments, the size of the single crystal germanium used in step one is 2 inches to 4 inches.

In some embodiments, the length of the cylinder obtained in step one is 110mm to 120 mm.

In some embodiments, the thickness of the anvil in step two is 2cm to 5 cm.

In some embodiments, in the third step, the cutting procedure is to cut the cutting line along the longitudinal direction of the cylinder, and the cutting line is set to move from 111mm to 121mm to 0mm along the z-axis at a speed of 4mm/min to 6 mm/min; then moving the workpiece from 0mm to 111 mm-121 mm at a speed of 50 mm/min-60 mm/min, and then moving the workpiece along the x axis at a speed of 50 mm/min-60 mm/min; repeating for 2-6 times.

In some embodiments, the cut line has a diameter of 0.4mm to 0.6 mm.

In some embodiments, in step four, the cylinder is rotated by 90 ° or 270 °.

In some embodiments, in step four, the rectangular bar has a dimension of 15 × 15 × 110-120mm³Cross section of 15X 15mm²。

In some embodiments, the tumbling procedure in step five is to roll the rectangular bar into a cylinder with a diameter of 11.8 mm-12.2 mm, roll the rectangular bar into a truncated cone with an angle of 4 ° from 0 mm-20 mm from the head, and finally roll the rectangular bar with a diameter of 20 mm-110 mm and 121mm into a cylinder with a diameter of 9.0 mm-9.4 mm.

In some embodiments, in step six, the nitrogen concentration used is 9N.

The beneficial effects of this disclosure are as follows:

the application provides a preparation method of ultra-high-purity germanium single crystal seed crystals, the ultra-high-purity seed crystals are obtained by three times of pulling, and the cutting machine and the tumbling mill are combined, so that the prepared seed crystals are smooth and exquisite, good in coaxiality, high in efficiency and high in product rate, excessive waste materials are not generated except leftover materials, and the cost is saved.

Detailed Description

The method for preparing the ultra-high purity germanium single crystal seed according to the present disclosure is explained in detail below.

The application discloses a preparation method of ultra-high pure germanium single crystal seed crystals, which comprises the following steps: firstly, removing heads and tails of single crystal germanium, taking the middle of the single crystal germanium to obtain a cylinder, and detecting the purity and dislocation of two ends of the cylinder, wherein the head label with better purity and dislocation is a tail part, and the head label with poorer purity and dislocation is a head part; fixing any one end of the cylinder on a cutting board, and putting the fixed cylinder and the cutting board into a cutting machine; setting a cutting program for the cutting machine, and cutting the cylinder; rotating the cylinder, and repeating the cutting procedure in the third step to obtain rectangular strips; putting the rectangular bar into a tumbling mill, setting a tumbling procedure, and obtaining seed crystals after tumbling; step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen; step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the purity higher than that of the single crystal germanium in the step one, and pulling out the single crystal germanium; step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals; step nine, using the single crystal seed crystal obtained in the step eight to pull the ultra-high purity polycrystalline germanium material with the purity higher than that of the step seven, and pulling out single crystal germanium; step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals; step eleven, using the single crystal seed crystal obtained in the step ten to pull the ultra-high purity polycrystalline germanium material with the purity higher than that in the step nine, and pulling out single crystal germanium; and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high purity germanium single crystal seed crystal.

In step one, one end with high purity and low dislocation is selected as a tail for seeding. The purity of the seed crystal and dislocations affect the purity and dislocations of the pulled crystal, with higher purity of the seeding portion resulting in higher purity of the pulled crystal and lower dislocations resulting in lower dislocations of the pulled crystal.

In some embodiments, the size of the single crystal germanium used in step one is 2-4 inches.

In some embodiments, the length of the cylinder obtained in step one is 110mm to 120 mm.

In some embodiments, the thickness of the anvil in step two is 2cm to 5 cm.

In some embodiments, in the third step, the cutting procedure is to cut the cutting line longitudinally along the cylinder, the cutting line is set to move from 121mm to 0mm along the z-axis at a speed of 4-6 mm/min and then from 0mm to 121mm along the z-axis at a speed of 50-60 mm/min, and then move 15mm along the x-axis at a speed of 50-60 mm/min; repeating for 2-6 times. The equipment is automatically cut according to the size of the crystal, and the operation is carried out once without cutting a knife.

In the whole process of the application, the cutting machine and the tumbling mill are used for combined manufacture, so that the manufacture efficiency of the seed crystal is improved.

In some embodiments, the diameter of the cutting line is 0.4-0.6 mm, and the cutting speed is 4-6 mm/min. The wire is easy to break in the process of cutting the wire too finely, and the loss of germanium materials is more when the wire is too coarse; too slow speed has low effect, and too fast speed is easy to break.

In some embodiments, in step four, the cylinder is rotated by 90 ° or 270 °. The number of cutters for cutting at the angle is minimum, and raw materials are not easy to waste.

In some embodiments, in step four, the rectangular bar size is 15 × 15 × 115mm³Cross section of 15X 15mm²If the section is too large, germanium materials are wasted, and if the section is too small, the germanium materials cannot be rolled into seed crystals with the diameter within the required range.

In some embodiments, the tumbling procedure in step five is to roll the rectangular bar into a cylinder with a diameter of 11.8 mm-12.2 mm, roll the rectangular bar into a truncated cone with a 4 ° offset angle from 0 mm-20 mm from the head, and finally roll the rectangular bar into a cylinder with a diameter of 9.0 mm-9.4 mm from 20 mm-110 mm and 120mm to obtain the seed crystal.

In some embodiments, in step six, the nitrogen concentration used is 9N. Thus, the obtained seed crystal has high purity and no pollution.

[ test procedures and test results ]

Example 1

Firstly, removing heads, tails and middles of 2-inch single crystal germanium with the carrier concentration of E12 grade to obtain a cylinder with the length of 110mm, and detecting the purity and dislocation of two ends of the cylinder, wherein the head with better purity and dislocation is marked as a tail, and the head with poorer purity and dislocation is marked as a head;

fixing any one end of the cylinder on a cutting board, and putting the fixed cylinder and the cutting board with the thickness of 2cm into a cutting machine;

setting a cutting program for the cutting machine, enabling the cutting line with the diameter of 0.4mm to cut along the longitudinal direction of the cylinder, and setting the cutting line to move from 111mm to 0mm along the z axis at the speed of 4 mm/min; then moving the workpiece from 0mm to 111mm at a speed of 50mm/min, and then moving the workpiece along the x axis at a speed of 15 mm/min; repeating for 2 times and stopping;

step four, rotating the cylinder by 90 degrees, repeating the cutting procedure in the step three to obtain the product with the size of 15 multiplied by 110mm³A rectangular bar of (a);

putting the rectangular strips into a tumbling mill, setting a tumbling process, rolling the rectangular strips into a cylinder with the diameter of 11.8mm, rolling the rectangular strips into a truncated cone with the angle of 4 degrees from 0mm to 20mm from the head, and rolling the rectangular strips into a cylinder with the diameter of 9.0mm from 20mm to 110mm to obtain seed crystals with the carrier concentration of E12;

step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen with the purity of 9N;

step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the carrier concentration of E11, and pulling out single crystal germanium with the carrier concentration of E11;

step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals with the carrier concentration of E11;

step nine, pulling a polycrystalline germanium material with the carrier concentration of E10 by using the single crystal seed crystal obtained in the step eight, and pulling single crystal germanium with the carrier concentration of E11-E10;

step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals with the carrier concentration of E11-E10;

eleven, using the single crystal seed crystal obtained in the step ten to pull the polycrystalline germanium material with the carrier concentration of E10-E9 and pull out single crystal germanium with the carrier concentration of E10-E9;

and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high pure germanium single crystal seed crystal with the carrier concentration of E10-E9.

Example 2

Step one, removing heads, tails and middles of 3 inches of single crystal germanium with the carrier concentration of E12 grade to obtain a cylinder with the length of 115mm, detecting the purity and dislocation of two ends of the cylinder, wherein the head with better purity and dislocation is marked as a tail, and the head with poorer purity and dislocation is marked as a head;

fixing any one end of the cylinder on a chopping board with the thickness of 2cm, and putting the fixed cylinder and the chopping board into a cutting machine;

setting a cutting program for the cutting machine, enabling the cutting line with the diameter of 0.5mm to cut along the longitudinal direction of the cylinder, and setting the speed of the cutting line to move from 116mm to 0mm along the z axis at 5 mm/min; then moving the workpiece from 0mm to 116mm at the speed of 55mm/min, and then moving the workpiece along the x axis at the speed of 15 mm/min; repeating for 4 times to stop;

step four, rotating the cylinder by 90 degrees, repeating the cutting procedure in the step three to obtain the product with the size of 15 multiplied by 110mm³A rectangular bar of (a);

putting the rectangular strips into a tumbling mill, setting a tumbling process, rolling the rectangular strips into a cylinder with the diameter of 12.0mm, rolling the rectangular strips into a truncated cone with the angle of 4 degrees from 0mm to 20mm from the head, and rolling the rectangular strips into a cylinder with the diameter of 9.2mm from 20mm to 115mm to obtain seed crystals with the carrier concentration of E12;

step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen with the purity of 9N;

step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the carrier concentration of E11, and pulling out single crystal germanium with the carrier concentration of E11;

step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals with the carrier concentration of E11;

step nine, pulling the polycrystalline germanium material with the carrier concentration of E10 by using the single crystal seed crystal obtained in the step eight, and pulling out single crystal germanium with the carrier concentration of E11-E10;

step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals with the carrier concentration of E11-E10;

step eleven, pulling the polycrystalline germanium material with the carrier concentration of E10-E9 by using the single crystal seed crystal obtained in the step eleven, and pulling out single crystal germanium with the carrier concentration of E10-E9;

and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high pure germanium single crystal seed crystal with the carrier concentration of E10-E9.

Example 3

Firstly, removing heads, tails and middles of 4-inch single crystal germanium with the carrier concentration of E12 grade to obtain a cylinder with the length of 120mm, and detecting the purity and dislocation of two ends of the cylinder, wherein the head with better purity and dislocation is marked as a tail, and the head with poorer purity and dislocation is marked as a head;

fixing any one end of the cylinder on a chopping board with the thickness of 2cm, and putting the fixed cylinder and the chopping board into a cutting machine;

setting a cutting program for the cutting machine, enabling the cutting line with the diameter of 0.6mm to cut along the longitudinal direction of the cylinder, and setting the speed of the cutting line to be 6mm/min when the cutting line moves from 121mm to 0mm along the z axis; then moving the workpiece from 0mm to 121mm at the speed of 60mm/min, and then moving the workpiece along the x axis at the speed of 60mm/min for 15 mm; repeating for 6 times to stop;

step four, rotating the cylinder by 90 degrees, repeating the cutting procedure in the step three to obtain the product with the size of 15 multiplied by 120mm³Rectangular strips;

putting the rectangular strips into a tumbling mill, setting a tumbling process, rolling the rectangular strips into a cylinder with the diameter of 12.2mm, rolling the rectangular strips into a truncated cone with the angle of 4 degrees from 0mm to 20mm from the head, and rolling the rectangular strips into a cylinder with the diameter of 9.4mm from 20mm to 121mm to obtain seed crystals with the carrier concentration of E12;

step six, corroding the seed crystals in the step five in a thousand-level or more clean room, and drying the seed crystals by using high-purity nitrogen;

step seven, using the seed crystal dried in the step six, then pulling the polycrystalline germanium material with the carrier concentration of E11, and pulling out single crystal germanium with the carrier concentration of E11;

step eight, repeating the step one to the step six by using the single crystal germanium obtained in the step seven to obtain single crystal seed crystals with the carrier concentration of E11;

step nine, pulling a polycrystalline germanium material with the carrier concentration of E10 by using the single crystal seed crystal obtained in the step eight, and pulling single crystal germanium with the carrier concentration of E11-E10;

step ten, repeating the step one to the step six by using the single crystal germanium in the step eight to obtain single crystal seed crystals with the carrier concentration of E11-E10;

eleven, using the single crystal seed crystal obtained in the step ten to pull the polycrystalline germanium material with the carrier concentration of E10-E9 and pull out single crystal germanium with the carrier concentration of E10-E9;

and step twelve, repeating the step one to the step six by using the single crystal germanium in the step eleven to obtain the ultra-high pure germanium single crystal seed crystal with the carrier concentration of E10-E9.

The above-disclosed features are not intended to limit the scope of practice of the present disclosure, and therefore, all equivalent variations that are described in the claims of the present disclosure are intended to be included within the scope of the claims of the present disclosure.