Gallium arsenide crystal growth
US4840699A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1987 |
| Grant date | Jun 20, 1989 |
| Priority date | — |
| Expiry date | Dec 28, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S117/902
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A process that, without doping of PBN crucibles, produces semi-insulating GaAs having low, or essentially no, dislocation density; and in which the crystal may be in situ annealed after growth. The process is a variant of the Heat Exchanger Method (HEM) disclosed in U.S. Pat. No. 3,898,051. Crack-free, semi-insulating GaAs crystals having low dislocation density are grown from presynthesized undoped GaAs meltstock in sealed quartz (vitreous silica) crucibles, without the need for an encapsulant. One aspect of the invention features seeded growth of <100> orientation crystals having a dislocation density 1-2 orders of magnitude less than that of the seed; in another aspect, crystals having fewer than 500 dislocations/cam.sup.2 in their center column are grown without a seed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.