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

Method for casting silicon ingot

A silicon ingot and polycrystalline silicon technology, applied in the field of silicon ingot casting, can solve the problems of crystal growth failure and floating, and achieve the effect of size increase

Inactive Publication Date: 2015-06-10
PROPOWER RENEWABLE ENERGY SHANGHAI
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, since the density of solid silicon is lower than that of liquid silicon, the solid silicon placed at the bottom of the crucible may float up after being wetted by contact with liquid silicon, resulting in the failure of induced crystal growth.

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 for casting silicon ingot
  • Method for casting silicon ingot
  • Method for casting silicon ingot

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0025] like figure 1 Shown is the flow chart of the method of the embodiment of the present invention, the casting method of the silicon ingot of the embodiment of the present invention comprises the following steps:

[0026] Step one, such as figure 2 As shown, charging is carried out in the crucible 100:

[0027] Firstly, the base material 101 is laid on the bottom surface of the crucible 100, and the base material 101 includes pure polysilicon powder and additive powder. The particle size of the polycrystalline silicon powder is 500 mesh to 5000 mesh, and the thickness of the bottom layer raw material 101 is 0.1 mm to 5 mm. The additive powder is silica sol, or the additive powder is a mixture of fluosilicic acid and silicon dioxide, the particle size of the additive powder is 1000 mesh to 20000 mesh, and the purity is above 99.999%.

[0028] Next, lay the intermediate layer raw material 102 on the bottom layer raw material 101, and the described intermediate layer raw ...

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
particle sizeaaaaaaaaaa
thicknessaaaaaaaaaa
particle sizeaaaaaaaaaa
Login to View More

Abstract

The invention discloses a method for casting a silicon ingot, comprising the steps of: placing materials in a crucible, wherein a bottom-layer raw material comprises polycrystalline silicon powder, a middle-layer raw material is formed by splicing monocrystalline silicon wafers, and an upper-layer raw material is a polycrystalline silicon material; placing the crucible into an ingot casting furnace, vacuumizing, and sintering the polycrystalline silicon powder so that the monocrystalline silicon wafers are fixed; controlling a vertical temperature gradient in the furnace, so that the upper parts of the monocrystalline silicon wafers are melted and the polycrystalline silicon material is melted; and controlling the vertical temperature gradient in the furnace, so that crystal grains grow upwards along unmelted monocrystalline silicon wafers and the silicon ingot is obtained. By using the method for casting the silicon ingot, the crystal grain size of the silicon ingot can be improved, the photoelectric conversion efficiency of a silicon battery plate made of the silicon ingot is improved, and the preparation cost can be reduced.

Description

technical field [0001] The invention relates to the field of photovoltaic product manufacturing, in particular to a method for casting silicon ingots. Background technique [0002] The main raw material of solar cells is silicon crystal, including monocrystalline silicon and polycrystalline silicon. Monocrystalline silicon is mainly prepared by the Czochralski method, which is characterized by complete crystal structure, low number of crystal defects, and high photoelectric conversion efficiency of the prepared silicon cells. However, the cost of silicon cells prepared by this method is relatively high, and the production efficiency is low. Due to the characteristics of its production technology, the monocrystalline silicon ingot produced by the Czochralski method is cylindrical, and the utilization rate of the material is low in the process of cutting into square cells. [0003] Polysilicon is generally prepared by directional solidification, using a square crucible, whic...

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 Patents(China)
IPC IPC(8): C30B11/00C30B28/06C30B29/06
Inventor 史珺孙文彬
Owner PROPOWER RENEWABLE ENERGY SHANGHAI