Compound semiconductor substrate including nitride semiconductor layer having varying threading dislocation densities
US12230679B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 2019 |
| Grant date | Feb 18, 2025 |
| Priority date | — |
| Expiry date | Sep 15, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/53
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A compound semiconductor substrate has a Si (silicon) substrate, a first Al nitride semiconductor layer which is a graded layer formed on the Si substrate and whose Al concentration decreases as the distance from the Si substrate increases along the thickness direction, a GaN (gallium nitride) layer formed on the first Al nitride semiconductor layer and having a lower average Al concentration than the average Al concentration of the first Al nitride semiconductor layer, and a second Al nitride semiconductor layer formed on the GaN layer and having a higher average Al concentration than the average Al concentration of the GaN layer. The threading dislocation density at any position in the thickness direction within the second Al nitride semiconductor layer is lower than the threading dislocation density at any position in the thickness direction within the first Al nitride semiconductor layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.