Apparatus for removing deposits from backside and end edge of semiconductor wafer while preventing removal of materials from front surface of wafer
US5213650A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1991 |
| Grant date | May 25, 1993 |
| Priority date | — |
| Expiry date | Sep 13, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3065
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An apparatus is disclosed for removing one or more materials deposited on the backside and end edges of a semiconductor wafer which includes means for urging the front side of the wafer against a faceplate in a vacuum chamber; means for flowing one or more gases through a space maintained between the front side of the wafer and the faceplate; and means for forming a plasma in a gap maintained between the backside of the wafer and susceptor to remove materials deposited on the backside and end edge of the wafer; the gas flowing through the space between the front side of the wafer and the faceplate acting to prevent the plasma from removing materials on the front side of the wafer. In a preferred embodiment, the front side of the wafer is spaced from the faceplate by providing a generally circular recess in the faceplate having a depth corresponding to the desired spacing and having a diameter larger than the diameter of the wafer with spacing means in the recessed area to engage portions of the wafer to permit gas to flow through the recess and around the end edge of the wafer to inhibit removal of materials from the front surface of the wafer by the plasma.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.