Method to prepare semi-conductor device comprising a selective etching of a silicium—germanium layer
US9076732B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 2012 |
| Grant date | Jul 7, 2015 |
| Priority date | — |
| Expiry date | Sep 27, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31111
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a method for manufacturing a semiconductor device by wet-process chemical etching, the device comprising at least one layer of silicon (Si) and at least one layer of silicon-germanium (SiGe) and at least one layer of photosensitive resin forming a mask partly covering the layer of silicon-germanium (SiGe) and leaving the layer of silicon-germanium uncovered in certain zones, characterized in that it comprises a step of preparation of an etching solution, having a pH between 3 and 6, from hydrofluoric acid (HF), hydrogen peroxide (H2O2), acetic acid (CH3COOH) and ammonia (NH4OH), and a step of stripping of the layer of silicon-germanium (SiGe) at least at the said zones by exposure to the said etching solution. The invention will be applicable for the manufacture of integrated circuits and more precisely of transistors. In particular, for optimization of CMOS transistors of the latest generation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.