A kind of method for heterogenous growth of aln on sic seed crystal by pvt method

A seed crystal and heterogeneous technology, which is applied in the direction of single crystal growth, single crystal growth, crystal growth, etc., can solve the problems of high impurity content, cracks, and low single crystal rate of AlN seed crystal, so as to achieve low impurity content and guarantee The effect of high flatness and single crystal rate

Active Publication Date: 2022-07-22
PEKING UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] In order to overcome the above-mentioned problems in the prior art, the present invention provides a new method for heterogeneously growing AlN on SiC seed crystals by physical vapor transport method (PVT method), which is a bonding method using vapor-saturated microcavity and AlN AlN powder (the main component is AlN powder, which can be sublimated similar to AlN source powder) inhibits the initial decomposition and sublimation of SiC while promoting the middle and late sublimation of SiC to prepare the growth technology of large-sized AlN seed crystals, which can significantly improve the heterogeneous growth on SiC single crystals The existing methods of obtaining AlN seed crystals with the same size have problems such as low single crystal rate of AlN seed crystals, high impurity content, poor crystal quality and cracks

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 kind of method for heterogenous growth of aln on sic seed crystal by pvt method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Example 1 One-step growth

[0036] 1) SiC seed crystal fixation:

[0037] Clean the seed crystal holder polished on one side, the SiC seed crystal and ring polished on both sides, place the seed crystal on the polished surface of the seed crystal holder to ensure a good fit, apply an appropriate amount of AlN adhesive evenly around the seed crystal, and then apply it to the seed crystal. A ring is placed on the crystal to press the edge of the seed crystal and the adhesive to ensure that the seed crystal holder, the seed crystal and the ring are concentric, and the adhesive is solidified, which can inhibit the decomposition and sublimation of the SiC side;

[0038] 2) AlN polycrystalline spacer is fixed:

[0039] The AlN polycrystalline ingot is cut, ground and polished to obtain an AlN polycrystalline wafer with a size similar to that of the SiC seed crystal. The edge of the AlN polycrystalline ingot is bonded to the placed ring with an adhesive, and it is also kept con...

Embodiment 2

[0048] Example 2 Two-step growth

[0049] 1) SiC seed crystal fixation:

[0050] Clean the seed crystal holder polished on one side, the SiC seed crystal and ring polished on both sides, place the seed crystal on the polished surface of the seed crystal holder to ensure a good fit, apply an appropriate amount of AlN adhesive evenly around the seed crystal, and then apply it to the seed crystal. A ring is placed on the crystal to press the edge of the seed crystal and the adhesive to ensure that the seed crystal holder, the seed crystal and the ring are concentric, and the adhesive is solidified, which can inhibit the decomposition and sublimation of the SiC side;

[0051] 2) AlN polycrystalline spacer is fixed:

[0052] The AlN polycrystalline ingot is cut, ground and polished to obtain an AlN polycrystalline wafer with a size similar to that of the SiC seed crystal. The edge of the AlN polycrystalline ingot is bonded to the placed ring with an adhesive, and it is also kept c...

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 discloses a method for heterogeneously growing AlN on a SiC seed crystal by using a physical vapor transport method. A crucible structure including a vapor-saturated microcavity is designed, and the interior of the microcavity can be evacuated and inflated; The vapor-saturated microcavity suppresses the forward decomposition and sublimation of SiC in the initial stage and realizes the growth of AlN. The lateral sublimation of SiC in the initial stage is suppressed by the adhesive covering with weak pores, and the AlN polycrystalline spacer is gradually back-sublimated and deposited on the surface of SiC; After the sublimation of the polycrystalline spacer disappears, the Al atoms obtained by the sublimation of the AlN source powder are transported to the growth surface; The AlN binder sublimates away from the crucible area, so that the SiC is sublimated and decomposed laterally, and the SiC seed crystal layer gradually disappears, thereby obtaining an AlN seed crystal without SiC. By adopting the method of the invention, crack-free AlN seed crystals with high single crystal rate and low impurity content can be obtained.

Description

technical field [0001] The invention relates to the technical field of crystal growth, in particular to a method for heterogeneously growing AlN on a SiC seed crystal by using a physical vapor transport method (PVT method). Background technique [0002] The lattice mismatch and thermal mismatch between AlN (aluminum nitride) and high Al composition AlGaN (aluminum gallium nitride) are very small. Reduce the dislocation density of the epitaxial layer to improve the lattice quality. Therefore, AlN single crystal has become the optimal substrate for epitaxial growth of AlN and AlGaN structures to fabricate deep ultraviolet optical elements. At the same time, AlN single crystal has many excellent properties, including high breakdown field strength, high thermal conductivity, high hardness, excellent electrical properties, etc. It is one of the important substrate materials for the preparation of power electronic devices that work under extreme conditions such as high temperature...

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): C30B23/02C30B29/40
CPCC30B23/025C30B29/403
Inventor 吴洁君赵起悦于彤军王泽人韩彤沈波
Owner PEKING UNIV
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