Method of reducing wafer particles after partial saw
US5817569A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 1997 |
| Grant date | Oct 6, 1998 |
| Priority date | — |
| Expiry date | May 8, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/78
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of fabricating a monolithic device, preferably a micromechanical device, from a wafer (20) by carefully selecting the composition of two or more layers of photoresist (52,54). The present invention comprises choosing compatible photoresist layers to avoid generating defects in the layers of photoresist which could allow a wet chemical HF acid etch process to damage an underlying micromechanical device. The present invention allows a very strong solution of hydrofluoric acid to be utilized to remove particles and debris after a partial-saw process, and to remove a damaged portion of an underlying CMOS layer (22) at a region (68) proximate a kerf (62). Using an HF solution having a concentration of about 6% is desired. The present invention substantially improves the yield of micromechanical devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.