Method for forming a contact hole on a semiconductor wafer
US6147007A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1999 |
| Grant date | Nov 14, 2000 |
| Priority date | — |
| Expiry date | Jun 11, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76814
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method of forming a contact hole on the semiconductor wafer. The semiconductor wafer comprises, in ascending order, a substrate, a silicon nitride layer, a silicon oxide layer, and a photo-resist layer. There is a hole in the photo-resist layer. The method comprises: (1) performing a first anisotropic etching process in a downward direction to remove the silicon oxide layer under the hole down to the surface of the silicon nitride layer to form a recess; (2) performing an in-situ plasma cleaning process to entirely remove the polymer material remaining at the bottom of the recess; (3) performing an in-situ second anisotropic etching process in a downward direction to remove the silicon nitride layer from the bottom of the recess down to the surface of the substrate to form the contact hole; (4) performing another in-situ cleaning process to entirely remove the polymer material remaining at the bottom of the contact hole.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.