Method for substrate pretreatment to achieve high-quality III-nitride epitaxy
US8728938B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2012 |
| Grant date | May 20, 2014 |
| Priority date | — |
| Expiry date | Jun 26, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC30B29/406
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method for producing a modified surface of a substrate that stimulates the growth of epitaxial layers of group-III nitride semiconductors with substantially improved structural perfection and surface flatness. The modification is conducted outside or inside a growth reactor by exposing the substrate to a gas-product of the reaction between hydrogen chloride (HCl) and aluminum metal (Al). As a single-step or an essential part of the multi-step pretreatment procedure, the modification gains in coherent coordination between the substrate and group-III nitride epitaxial structure to be deposited. Along with epilayer, total epitaxial structure may include buffer inter-layer to accomplish precise substrate-epilayer coordination. While this modification is a powerful tool to make high-quality group-III nitride epitaxial layers attainable even on foreign substrates having polar, semipolar and nonpolar orientation, it remains gentle enough to keep the surface of the epilayer extremely smooth. Various embodiments are disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.