Monolithic integrated lattice mismatched crystal template and preparation method thereof

Patent metadata

Field	Value
Publication number	US-9890472-B2
Application number	US-201214362130-A
Country	US
Kind code	B2
Filing date	Apr 6, 2012
Priority date	Dec 2, 2011
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

The present invention provides a monolithic integrated lattice mismatched crystal template and a preparation method thereof by using low-viscosity material, the preparation method for the crystal template includes: providing a first crystal layer with a first lattice constant; growing a buffer layer on the first crystal layer; below the melting point of the buffer layer, growing a second crystal layer and a template layer by sequentially performing the growth process of a second crystal layer and the growth process of a first template layer on the buffer layer, or growing a template layer by directly performing a first template layer growth process on the buffer layer; melting and converting the buffer layer to an amorphous state, performing a second template layer growth process on the template layer grown by the first template layer growth process at the growth temperature above the glass transition temperature of the buffer layer, sequentially growing a template layer until the lattice of the template layer is fully relaxed. Compared to the prior art, the invention has advantages of simple preparation, achieving in various lattice constant material combinations on one substrate and low dislocation density, high crystal quality.

First claim

What is claimed is:

1. A preparation method for a monolithic integrated lattice mismatched by using low-viscosity material, characterized in that, includes:
providing a first crystal layer with a first lattice constant;
growing a buffer layer on the first crystal layer, the buffer layer being grown at a temperature below its melting point on the first crystal layer;
below the melting point of the buffer layer, performing a first template layer growth process for a template layer, growing the template layer on the buffer layer, wherein the template layer has a second lattice constant, which differs from the first lattice constant of the first crystal layer;
melting and converting the buffer layer to an amorphous state, performing a second template layer growth process for the template layer at a growth temperature above a glass transition temperature of the buffer layer, the template layer is sequentially grown until the lattice of the template layer is fully relaxed.

2. The preparation method for the crystal template according to claim 1 , characterized in that, prior to performing the first template layer growth process, further includes:
growing a second crystal layer on the buffer layer at a temperature below the melting point of the buffer layer, the second crystal layer has lattice mismatch relative to the buffer layer and is partially relaxed or strained.

3. The preparation method for the crystal template according to claim 2 , characterized in that, a melting point of the buffer layer is lower than a melting point of any one of the first crystal layer, the second crystal layer and the template layer of the crystal template.

4. The preparation method for the crystal template according to claim 2 , characterized in that, the total thickness of the second crystal layer and the template layer is greater than the thickness of the buffer layer.

5. The preparation method for the crystal template according to claim 4 , characterized in that, the thickness of the second crystal layer is smaller than the critical thickness of the infinitely thick template layer, or ensure that dislocations generated at a interface between the second crystal layer and the template layer bend towards to the second crystal layer.

6. The preparation method for the crystal template according to claim 1 , characterized in that, the buffer layer has a thickness of nanometer order, and is strained or partially or fully relaxed relative to the first crystal layer.

7. The preparation method for the crystal template according to claim 1 , characterized in that, the step of melting the buffer layer and then converting to an amorphous state is achieved by either of the following ways:
a. raising the growth temperature to above the melting point of the buffer layer, such that the buffer layer melts and converts to an amorphous state;
b. selectively melting the buffer layer to convert to an amorphous state by employing an external laser.

8. The preparation method for the crystal template according to claim 1 , characterized in that, the preparation method for the crystal template allows reuse during the same growth process.

9. The preparation method for the crystal template according to claim 1 , characterized in that, the preparation method for the crystal template is achieved by any of epitaxial growth methods including molecular beam epitaxy (MBE), metal-organic vapor phase epitaxy (MOVPE), liquid phase epitaxy (LPE), hot wall epitaxy (HWE), and modified deposition modes including droplet epitaxy, migration enhanced epitaxy, atomic layer epitaxy, and sputtering, pulsed laser deposition, and other crystal deposition technologies by using evaporation element or ion beam.

Assignees

• Wang Shumin
• Shanghai Inst Microsystem & Information Tech Cas

Inventors

• Wang Shumin

Classifications

• H10P14/3802

  Crystallisation or recrystallisation of non-monocrystalline semiconductor materials, e.g. regrowth · CPC title

• H10P14/3421

  Arsenides · CPC title

• H10P14/3222 Primary

  Antimonides · CPC title

• H10P14/3221

  Arsenides · CPC title

• H10P14/2911

  Arsenides · CPC title