Process for implanting a deep subcollector with self-aligned photo registration marks
US6656815B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2001 |
| Grant date | Dec 2, 2003 |
| Priority date | — |
| Expiry date | Jun 21, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of forming a BiCMOS device having a deep subcollector region and self-aligned alignment marks is provided. The inventive method includes the steps of: (a) lithographically forming a first patterned layer comprising a thick dielectric material on a surface of a material stack formed on a semiconductor substrate, the first patterned layer including at least one opening therein and the semiconductor substrate having at least an alignment area; (b) performing a high-energy/high-dose implant through the at least one opening and the material stack so as to form at least one deep subcollector region in the semiconductor substrate; (c) lithographically forming a second patterned layer (photoresist or dielectric) predominately outside the first patterned layer in the alignment area; and (d) etching through the material stack to form alignment marks in the underlying semiconductor substrate using the first patterned layer as an alignment mark mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.