Vertical ESD protection device
US8664080B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2012 |
| Grant date | Mar 4, 2014 |
| Priority date | — |
| Expiry date | Jun 12, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/1461
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for forming a vertical electrostatic discharge (ESD) protection device includes depositing a multi-layer n-type epitaxial layer on a substrate having p-type surface including first epitaxial depositing to form a first n-type epitaxial layer on the p-type surface, and second epitaxial depositing to form a second n-type epitaxial layer formed on the first n-type epitaxial layer. The first type epitaxial layer has a peak doping level which is at least double that of the second n-type epitaxial layer. A p+ layer is formed on the second n-type epitaxial layer. An etch step etches through the p+ layer and multi-layer n-type epitaxial layer to reach the substrate to form a trench. The trench is filled with a filler material to form a trench isolation region. A metal contact is formed on the p+ layer for providing contact to the p+ layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.