Patent · US Expired

Method for forming high voltage device

US6063674A · kind A · utility

6Cited by
8References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 28, 1998
Grant dateMay 16, 2000
Priority date
Expiry dateOct 28, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D64/516

Abstract

A method for forming high voltage devices is provided. A P-type semiconductor substrate is provided. An oxide layer is formed on the P-type semiconductor substrate. A first P-well and a second P-well are formed in the P-type semiconductor substrate. A first N-well is formed in the second p-well and a second N-well is formed in the first P-well. A field oxide layer on the second N-well and a gate oxide layer are formed on the P-type substrate. A polysilicon layer is formed and defined as a gate on the gate oxide layer across a portion of the field oxide layer and aportion of the first N-well. A source region is formed in the first N-well and a drain region is formed in the second N-well. A P.sup.+ -type doped region is formed between the substrate and the source region across a part of the first N-well within the second P-well.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.