Group-III nitride semiconductor freestanding substrate and manufacturing method of the same
US8102026B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 10, 2009 |
| Grant date | Jan 24, 2012 |
| Priority date | — |
| Expiry date | Jun 30, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/0254
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
To provide a group-III nitride semiconductor freestanding substrate, with carrier concentration of a peripheral part of a n-type group-III nitride semiconductor freestanding substrate set to be lower than the carrier concentration inside of the peripheral part. In this freestanding substrate, preferably value Δσ obtained by dividing a difference between a maximum value of the carrier concentration and a minimum value of the carrier concentration in a surface of the freestanding substrate by the maximum value of the carrier concentration is greater than 0.05, and the carrier concentration in any place in the surface of the freestanding substrate exceeds 5.0×1017 cm−3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.