Etching of chromium layers on photomasks utilizing high density plasma and low frequency RF bias
US7008877B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 2004 |
| Grant date | Mar 7, 2006 |
| Priority date | — |
| Expiry date | May 8, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/321
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a method and an apparatus for etching a photolithographic substrate. The photolithographic substrate is placed on a support member in a vacuum chamber. A processing gas for etching a material from the photolithographic substrate is introduced into the vacuum chamber, and a plasma is generated. An RF bias is supplied to the support member in the vacuum chamber through an RF bias frequency generator at or below the ion transit frequency. Exposed material is etched from the photolithographic substrate with improved CD Etch Linearity and CD Etch Bias since the low frequency bias allows the developed charge on the photolithographic substrate, generated by the plasma, to dissipate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.