Method for forming a fragile layer inside of a single crystalline substrate preferably for making silicon-on-insulator wafers
US7148124B1 · kind B1 · utility
Inventor
Key dates
| Filing date | Nov 18, 2004 |
| Grant date | Dec 12, 2006 |
| Priority date | — |
| Expiry date | Jun 22, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76254
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Process for forming a fragile layer inside of a single crystalline substrate near one of the substrate surfaces. The fragile layer is created by collecting hydrogen in high concentration at a desired depth. The hydrogen layer is collected on a seed layer. The seed layer is formed by ion implantation of non-doping species and annealing. The implantation introduces defects that are capable to trap hydrogen, and annealing confines the seed layer making it flat and thin. Then protium hydrogen ions are implanted at elevated temperature. The protium implantation depth is bigger than the depth of the seed layer. The implanted protium moves to the seed layer and trap there. The process is useful for making silicon-on-insulator (SOI) wafers. SOI with an ultrathin superficial silicon layer of high quality can be obtained. Hydrogen can be implanted at high dose rate, and thus the SOI wafers can be manufactured with high throughput and low cost. SOI wafers also have high quality as superficial silicon does not contain microvoids.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.