Pyrolytic boron nitride crucible and method
US6670025B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 24, 2001 |
| Grant date | Dec 30, 2003 |
| Priority date | — |
| Expiry date | Jul 3, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/30
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method of forming a pyrolytic boron nitride (PBN) article and an article having layers of PBN separated by layers of PBN having a dopant of sufficient concentration to induce peeling, the steps of introducing vapors of ammonia and a gaseous boron halide in a suitable ratio into a heated furnace reactor to cause boron nitride to be deposited in layers on a substrate, with at least one gaseous dopant injected into furnace at controlled periodic interval(s) such that at least two selected layers of boron nitride are doped with said gaseous dopant(s) at a minimum average concentration of 2 atomic wt % at a depth ranging from 1000 to 2000 angstroms in each selected layer, and with the selected layers spaced apart about 0.1 micron to 100 microns apart.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.