Method for planarizing wafers
US4672023A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1985 |
| Grant date | Jun 9, 1987 |
| Priority date | — |
| Expiry date | Oct 21, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76232
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for filling indentations to planarize the surface of a wafer is disclosed. The method includes three steps: (1) coating the wafer surface with a layer of positive photoresist that fills the indentations and covers the surface of the wafer; (2) exposing the layer of photoresist to light or other radiation source of such intensity and duration that the layer of photoresist is exposed down to the surface of the wafer but not into the indentations; and (3) removing the exposed portion of the photoresist by using a developer, resulting in a planarized wafer containing indentations filled with unexposed photoresist. Once the wafer has been planarized by this method, overstructures can be formed over the top of the photoresist filled indentations.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.