Reducing leakage current in silicon-on-insulator substrates
US5352341A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 24, 1993 |
| Grant date | Oct 4, 1994 |
| Priority date | — |
| Expiry date | Jun 24, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3063
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
In accordance with the present invention, there is provided a method and structure which substantially reduce the leakage current between the surface layer and the substrate silicon that can be caused by the leakage pipes formed in the buried layer in a SIMOX process. A novel solution to this problem is to etch the silicon in these pipes by using an anodizing process. A preferred embodiment of this invention comprises the steps of exposing the surface layer (e.g. silicon 34) to an electrolytic solution (e.g dilute HF acid 38), and creating a potential difference between the substrate (e.g. silicon 30) and the solution, thereby causing current to flow through the leakage pipes (e.g. silicon 36) in the buried insulator layer (e.g. SiO.sub.2 32), thereby causing the solution to etch a portion of the surface silicon that is essentially above the leakage pipes, and to substantially etch the silicon in the leakage pipes, thus substantially reducing the leakage current paths between the substrate and the surface layer. Since the leakage current is generally detrimental to the performance of SIMOX devices, the clean removal of the silicon in the pipes will generally help improve the perfor…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.