Unlock instant, AI-driven research and patent intelligence for your innovation.

Process for producing single crystal and process for producing annealed wafer

Through multiple pulling methods and pulling condition correction technology, the problem of uneven quality of silicon single crystals has been solved, low-cost and efficient production of high-quality silicon single crystals has been achieved, and the defect density of the wafer has been optimized through nitrogen doping and heat treatment technology. Improved device performance and yield.

Inactive Publication Date: 2007-11-28
SHIN ETSU HANDOTAI CO LTD
View PDF7 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Furthermore, even if the nitrogen concentration is the same, the impact on the formation of Grown-in defects will be different due to the different G values, so it will be accompanied by major difficulties to obtain a large amount of nitrogen-doped wafers with uniform quality in a stable manner.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0062] A crucible with a diameter of 55 cm is set in the single crystal manufacturing device shown in Figure 1, and in order to use the CZ method to grow a silicon single crystal with a diameter of 20 cm, firstly, 120 kg of polycrystalline silicon raw material is placed in the crucible, and doped with nitrogen, so that the growth The nitrogen concentration of the silicon single crystal becomes 3 x 10 13 atoms / cm 3 . Then, the polycrystalline silicon raw material was melted by heating with a heater, and a silicon single crystal having a body length of 100 cm and a diameter of 20 cm was grown. Next, the polysilicon raw material with the same weight as the single crystal pulled up from the first one was added into the crucible, and the same type of crystal was repeatedly pulled by the multiple pulling method.

[0063] At this time, as shown in FIG. 2 , three kinds of single crystal pulling conditions were prepared according to the time counted from the start of heating by the h...

Embodiment 2

[0066] Next, when the silicon single crystal is grown, the flow rate of the inert gas, that is, argon (as a cleaning gas), is prepared to change the pattern 2' according to the passage of time (this inert gas is introduced from the gas inlet 10, and the After being drawn between the single crystal 3 and the gas rectifying cylinder 11, pass between the heat insulating member 12 and the melt surface of the raw material melt 4, and then flow out from the gas outlet 9), and start heating from the heater From 35 hours to 70 hours (the second one), use this pattern 2' (increase the gas flow rate by 15% compared with the first one), use the same pattern 1 as the first one for the pulling speed, and set other conditions to be the same as In the same manner as in Example 1, evaluation was performed in this manner. As a result, as shown in Figure 5, the density of defects near the surface can be uniformly distributed in the length direction of the single crystal, and the average value o...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
timeaaaaaaaaaa
timeaaaaaaaaaa
diameteraaaaaaaaaa
Login to View More

Abstract

The present invention is a method for producing a single crystal that is a multi-pulling method for pulling a plurality of single crystals 3 from a raw material melt 4 in a same crucible in a chamber by a Czochralski method, comprising steps of: pulling a single crystal 3 from a raw material melt 4; then additionally charging polycrystalline raw material in a residual raw material melt 4 without turning off power of a heater 7, and melting the polycrystalline raw material; then pulling a next single crystal 3; and repeating the steps and thereby pulling the plurality of single crystals 3; wherein in a case of setting a ratio of a pulling rate V and crystal temperature gradient G near a solid-liquid interface along a pulling axis direction when a straight body of the single crystal 3 is grown to be V / G, in order to control the V / G of each of the single crystals 3 to be pulled to a predetermined value, a pulling condition such as the pulling rate V is preliminarily modified according to an elapsed time from beginning of operation, before pulling the single crystal; and thereby the single crystal 3 having a desired defect region is grown.

Description

Technical Field [0001] This invention relates to a method for manufacturing a single crystal of silicon or the like, which is used to cut out silicon wafers or the like for use as substrates for semiconductor devices such as memory or CPUs. Background Technology [0002] In recent years, the integration density of semiconductor integrated circuits has increased significantly. To obtain integrated circuits with high performance, reliability, and yield, there has been a continuous demand for better precision and characteristics in both mechanical and electrical aspects. With this demand, the quality of silicon wafers used to manufacture devices such as semiconductor integrated circuits must meet more stringent conditions, thus requiring the manufacture of silicon wafers with superior crystal quality. Furthermore, due to the global impact of semiconductor integrated circuits and the expanding demand for them, silicon wafers are required to come in various forms, and there is a ne...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C30B15/20C30B33/02C30B29/06
CPCC30B29/06C30B15/203C30B15/14C30B15/20
Owner SHIN ETSU HANDOTAI CO LTD