Method of isotropically dry etching a poly/WSi.sub.x sandwich structure
US5110411A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 27, 1990 |
| Grant date | May 5, 1992 |
| Priority date | — |
| Expiry date | Apr 27, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/32137
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method of isotropically dry etching a WSi.sub.x /polysilicon sandwich structure on a silicon substrate wafer containing integrated semiconductor circuits. The method is conducted within a parallel plate reactor which in operation provides a substantially constant power density over the parallel plates. The reactor parallel plates are spaced a preselected separation distance from one another and a preselected amount of electrical power is applied thereto. Gases are injected to within the reactor provide a reactive gas mixture at a preselected pressure. The reactive gas mixture comprises SF.sub.6, Cl.sub.2, and O.sub.2 in approximate respective volume ratios of 7.0.+-.5%:5.0.+-.5%:4.0.+-.5%. The wafer is subjected to the reactive gas mixture at the preselected pressure for a preselected amount of time to selectively obtain a desired isotropic etch of the WSi.sub.x /polysilicon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.