Preparation of silicon substrate
US6402973B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 27, 2000 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Nov 14, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B2006/12176
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A silicon substrate is prepared by furnishing a silicon substrate (10) having a step (11) of at least 5 &mgr;m high on one surface, forming by high pressure heat oxidation an oxide film (12) which is thinner than the step, and removing the oxide film on the higher surface region until the silicon surface is exposed in the higher surface region while leaving the oxide film on the lower surface region. Because of excellent electrical properties, minimized warpage, a substantially constant oxygen concentration, and a definitely ascertainable oxide-silicon boundary, the silicon substrate is suitable for use in optical waveguide devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.