Aluminum nitride bulk crystals having high transparency to untraviolet light and methods of forming them
US9447519B2 · kind B2 · utility
6Cited by
119References
34Claims
0Family size
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Key dates
| Filing date | Apr 16, 2015 |
| Grant date | Sep 20, 2016 |
| Priority date | — |
| Expiry date | Apr 27, 2035 |
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.