Self aligned poly emitter bipolar technology using damascene technique
US5904536A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 1, 1998 |
| Grant date | May 18, 1999 |
| Priority date | — |
| Expiry date | May 1, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S148/011
Abstract
A polysilicon emitter of a bipolar device is formed utilizing a self-aligned Damascene technique. An oxide mask is patterned over epitaxial silicon implanted to form the intrinsic base. The oxide mask is then etched to form a window. Polysilicon is uniformly deposited over the oxide mask and into the window. The polysilicon is then polished to remove polysilicon outside of the window. Etching of the oxide mask follows, with good selectivity of oxide over silicon. This selectivity produces a polysilicon emitter atop an intrinsic base, the base flush with the silicon surface rather than recessed because of overetching associated with conventional processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.