Low defect axially grown single crystal silicon carbide
US6562130B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 2001 |
| Grant date | May 13, 2003 |
| Priority date | — |
| Expiry date | May 4, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1004
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method and apparatus for axially growing single crystal silicon carbide is provided. Utilizing the system, silicon carbide can be grown with a dislocation density of less than 104 per square centimeter, a micropipe density of less than 10 per square centimeter, and a secondary phase inclusion density of less than 10 per cubic centimeter. As disclosed, a SiC source and a SiC seed crystal of the desired polytype are co-located within a crucible, the growth zone being defined by the substantially parallel surfaces of the source and the seed in combination with the sidewalls of the crucible. Prior to reaching the growth temperature, the crucible is evacuated and sealed, either directly or through the use of a secondary container housing the crucible. The crucible is comprised of tantalum or niobium that has been specially treated. As a result of the treatment, the inner surfaces of the crucible exhibit a depth variable composition of Ta—Si—C or Nb—Si—C that is no longer capable of absorbing SiC vapors, thus allowing the vapor-phase composition within the crucible to be close to the SiC—Si system with the partial pressure of Si-vapor slightly higher than …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.