Aluminum nitride bulk crystals having high transparency to ultraviolet light and methods of forming them
US9034103B2 · kind B2 · utility
2Cited by
102References
35Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2010 |
| Grant date | May 19, 2015 |
| Priority date | — |
| Expiry date | Jan 24, 2034 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2982
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
In various embodiments, methods of forming single-crystal AlN include providing a substantially undoped polycrystalline AlN ceramic having an oxygen concentration less than approximately 100 ppm, forming a single-crystal bulk AlN crystal by a sublimation-recondensation process at a temperature greater than approximately 2000° C., and cooling the bulk AlN crystal to a first temperature between approximately 1500° C. and approximately 1800° C. at a first rate less than approximately 250° C./hour.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.