A method for preparing silicon carbide single crystal based on controllable growth center

A technology of silicon carbide single crystal and silicon carbide seed is applied in the field of preparing silicon carbide single crystal based on a controllable growth center, which can solve the problems of increasing the probability of crystal cracking, reducing the yield of single crystal, and non-uniform polymorphism, and achieving Small internal stress, improved electrical uniformity, and small residual internal stress

Active Publication Date: 2021-02-26
HEBEI SYNLIGHT CRYSTAL CO LTD +1
View PDF2 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this technology is difficult to achieve the expected effect in actual operation. There are two main reasons: 1. When the facet is removed by partial rolling, the force on the crystal will be seriously uneven, which will greatly increase the cracking probability of the crystal and seriously reduce it. 2. In order to keep the facets at the periphery of the required diameter, a very flat temperature field needs to be adjusted during the growth process, but the flat temperature field brings about the formation of multiple layers between the atmosphere deflector and the seed crystal. Crystal, polycrystalline crystal form is generally not single, it will swallow part of the normal diameter crystal, if the convex temperature field is used, the growth facet will appear inside the crystal and it is difficult to remove

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
  • A method for preparing silicon carbide single crystal based on controllable growth center
  • A method for preparing silicon carbide single crystal based on controllable growth center
  • A method for preparing silicon carbide single crystal based on controllable growth center

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0055] (1) Grinding and polishing a 4-inch silicon carbide seed crystal with a large diameter of 4° (diameter 105 mm) on both sides, so that the surface roughness is less than 0.3 nm and the flatness is 10 μm, and a silicon carbide seed crystal with a thickness of 500 μm is obtained. Then the surface is cleaned and packaged for use.

[0056] (2) Place a deflected growth component deflector in the powder and growth chamber: open four slots inside the graphite crucible tube, place four deflectors in the slots and fix them so that the deflectors The powder is divided into 3 regions with different volumes, and the part of the deflector located in the growth chamber is used to adjust the inclination angle of the component flow direction; the upper inclination angle of the deflector is 65 °, and the extension line of the deflector 5a is in line with the The edges of the large-diameter seed crystals just intersect, and the deflector not only plays the role of separating the silicon c...

Embodiment 2

[0063] (1) Grinding and polishing a 4-inch silicon carbide seed crystal with a large diameter of 5° (diameter 105 mm) on both sides, so that the surface roughness is less than 0.3 nm, and the flatness is 10 μm, and a silicon carbide seed crystal with a thickness of 500 μm is obtained. Then the surface is cleaned and packaged for use.

[0064] (2) Place a deflected growth component deflector in the powder and growth chamber: open four slots inside the graphite crucible tube, place four deflectors in the slots and fix them so that the deflectors The powder is divided into 3 different volume regions, and the part of the deflector located in the growth chamber is used to adjust the inclination angle of the component flow direction; the upper inclination angle of the deflector is 70 °, and the extension line of the deflector 5a is in line with the The edges of the large-diameter seed crystals just intersect, and the deflector not only plays the role of separating the silicon carbid...

Embodiment 3

[0070] (1) Grind and polish the 8-inch silicon carbide seed crystal with a large diameter of 8° on both sides, so that the surface roughness is less than 0.3nm, and the flatness is 10μm, and a silicon carbide seed crystal with a thickness of 500μm is obtained, and then the surface is cleaned. Clean and pack for use.

[0071] (2) Place a deflected growth component deflector in the powder and growth chamber: open four slots inside the graphite crucible tube, place four deflectors in the slots and fix them so that the deflectors The powder is divided into 3 regions with different volumes, and the part of the deflector located in the growth chamber is used to adjust the inclination angle of the component flow direction; the inclination angle of the upper part of the deflector is 75 °, and the extension line of the deflector 5a is in line with the The edges of the large-diameter seed crystals just intersect, and the deflector not only plays the role of separating the silicon carbid...

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
surface roughnessaaaaaaaaaa
thicknessaaaaaaaaaa
surface roughnessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing a silicon carbide single crystal based on a controllable growth center, belonging to the field of crystal growth. The present invention adjusts the transmission direction of the growth component flow and the flow density of the transport component by placing a deflected growth component flow guiding device in the powder and the growth chamber, preferentially forming a long and narrow growth center facet and keeping it at the edge of the growth surface Position, so that a balanced step flow growth mode can be maintained within the required single crystal diameter, and the crystal form of the seed crystal can be completely maintained, and finally a high-quality silicon carbide crystal with a single crystal form can be obtained. The high-quality silicon carbide single crystal prepared by the method of the present invention can be widely used in power electronics fields such as new energy electric vehicles, locomotive traction, industrial automation, uninterruptible power supplies, high-power charging piles, and energy Internet.

Description

technical field [0001] The invention relates to the technical field of crystal growth, in particular to a method for preparing a silicon carbide single crystal based on a controllable growth center. Background technique [0002] Silicon carbide (SiC) crystal is a group IV-IV compound material with unique physical and chemical properties. It has a tetrahedral structure formed by densely packed carbon atoms and silicon atoms, which makes silicon carbide materials exhibit high hardness, high thermal conductivity, high radiation resistance, high temperature resistance and strong chemical stability. And as an emerging third-generation semiconductor material, silicon carbide has shown a large band gap, high breakdown electric field and high saturation carrier mobility. These excellent properties enable it to be widely used in power electronics fields such as new energy electric vehicles, locomotive traction, industrial automation, uninterruptible power supplies, high-power chargi...

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): C30B29/36C30B23/00
CPCC30B23/002C30B29/36
Inventor 张福生杨昆路亚娟刘新辉牛晓龙崔景光尚远航
Owner HEBEI SYNLIGHT CRYSTAL CO LTD
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