Method and equipment for removing phosphorus and metal impurities in ganister sand through vacuum induction melting

A technology for vacuum induction smelting and metal impurities, applied in non-metallic elements, chemical instruments and methods, silicon compounds, etc., can solve the problems of limited public content, no induction smelting silicon powder to purify polysilicon, etc. The effect of stable effect and simple method

Inactive Publication Date: 2011-09-07
DALIAN UNIV OF TECH
View PDF4 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the disclosure content in the current technology is limited, and there is no

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method and equipment for removing phosphorus and metal impurities in ganister sand through vacuum induction melting
  • Method and equipment for removing phosphorus and metal impurities in ganister sand through vacuum induction melting

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] A method for vacuum induction smelting to remove phosphorus and metal impurities in silicon powder. First, in a high vacuum state, use induction heating to melt silicon powder to remove phosphorus impurities in polysilicon, and then carry out ingot pulling, and use directional solidification technology to melt the silicon powder. removal of metal impurities.

Embodiment 2

[0029] Vacuum induction smelting equipment for removing phosphorus and metal impurities in silicon powder. The equipment consists of a vacuum furnace cover 8 and a furnace body 9 as a whole. A mechanical pump 22, a Roots pump 23 and a diffusion pump 24 are installed outside the furnace. The inside of the body is a vacuum chamber 25; there is a feeding port 4 above the furnace cover 8, and a gasket 3 is added above the feeding port 4 for sealing. With an external drive type baffle, the external drive type baffle is an L-shaped baffle, one end of the baffle is rotated and connected to the controller, the controller is installed outside the furnace, the discharge port is aligned with the melting crucible, and the melting crucible is placed in the insulation sleeve , the insulation cover 12 is positioned on the bracket 18 at the lower part of the furnace body, and is fixed by the positioning bolt 17. The graphite sleeve 11 is set in the insulation cover 12, and the graphite sleeve ...

Embodiment 3

[0031]Adopt the equipment described in embodiment 2 to remove phosphorus and metal impurities in silicon powder for production. The first step is to prepare materials: put a small amount of high-purity polysilicon material into the quartz crucible 15 as the base material for smelting; rotate the controller 1. Make the baffle 2 block the discharge hole of the hopper 6, and put the polysilicon powder 7 with a phosphorus content of 0.003% and a metal impurity content of 0.01% into the hopper 6, and the loading position shall not exceed the hopper vent hole 5 on the hopper 6 , and then cover the sealing cover 3;

[0032] The second step pretreatment: close the furnace cover 8, then carry out the vacuuming process, first turn on the mechanical pump 22, the Roots pump 23 to carry out the vacuum pre-extraction, when the vacuum degree of the vacuum chamber 25 reaches 5Pa, open the diffusion pump 24 to vacuum the vacuum chamber 25 internal vacuum pumped to 10 -3 Pa; Pass cooling water...

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

No PUM Login to view more

Abstract

The invention belongs to the field of polycrystalline silicon purification in the metallurgical method. The method for removing phosphorus and metal impurities in ganister sand through vacuum induction melting comprises the steps of firstly removing the phosphorus impurity in the polycrystalline silicon through smelting the ganister sand in the induction heating mode under high vacuum state, then conducting ingot stretching, and then removing the metal impurities in the ganister sand through the directional solidification technology. The method disclosed by the invention is simple, the ganister sand is smelted with good impurity removal effect and high removal efficiency since the phosphorus and metal impurities in the polycrystalline silicon are removed through the vacuum induction melting and directional solidification technology, the characteristic of high temperature of the inductance coil heating is effectively used; and the method is simple and easy, integrates the double effects of phosphorus removal and metal removal, is high in yield and stable in purification effect, and is suitable for mass industrial production.

Description

technical field [0001] The invention belongs to the technical field of polysilicon purification by metallurgy, in particular to a method for removing phosphorus and metal impurities in silicon powder by vacuum induction smelting, and also to its equipment. Background technique [0002] The global energy crisis has made energy utilization increasingly urgent. Solar energy, as a green, renewable and clean energy, will occupy an important position in the energy structure and become the energy guarantee for future development. Solar-grade polysilicon is an important material for solar energy utilization. However, in order to ensure the photoelectric conversion efficiency, the purity of solar-grade silicon is very high, and the impurity content in it should be lower than 0.1ppm. [0003] At present, there are two main ways to produce solar-grade polysilicon, one is to produce polysilicon through chemical methods; the other is to produce polysilicon through metallurgical methods. ...

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
IPC IPC(8): C01B33/037
Inventor 谭毅姜大川董伟郭校亮顾正庞大宇石爽
Owner DALIAN UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap