Method for the making of a transistor gate
US5185277A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 1991 |
| Grant date | Feb 9, 1993 |
| Priority date | — |
| Expiry date | Jun 12, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/95
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Disclosed is a method for making a mushroom gate for a microwave transistor. Three masking layers are deposited on the semiconductor body of a transistor. At least two of these masking layers are different and have selective solvents. After the opening of the external layer, the intermediate layer is dissolved with sub-etching with respect to the external layer, then the base of the gate is etched in the internal layer. The edges of the sub-etching prevent the metal deposited on the mask from adhering to the gate, thus facilitating the lift-off of the mask. Application to microwave transistors with symmetrical or disymmetrical mushroom gate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.