Electrostatic discharge protection device structure
US8304838B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 2011 |
| Grant date | Nov 6, 2012 |
| Priority date | — |
| Expiry date | Aug 23, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D89/611
Abstract
An electrostatic discharge protection device structure is disclosed, which comprises a semiconductor substrate and an N-type epitaxial layer arranged on the semiconductor substrate. At least one snapback cascade structure is arranged in the N-type epitaxial layer, wherein the snapback cascade structure further comprises first and second P-type wells arranged in the N-type epitaxial layer. First and second heavily doped areas arranged in the first P-type well respectively belong to opposite types. And, third and fourth heavily doped areas arranged in the second P-type well respectively belong to opposite types, wherein the second and third heavily doped areas respectively belong to opposite types and are electrically connected with each other. When the first heavily doped area receives an ESD signal, an ESD current flows from the first heavily doped area to the fourth heavily doped area through the first P-type well, the N-type epitaxial layer, and the second P-type well.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.