Please download the dossier by clicking on the dossier button x
×

Structure for ESD protection in semiconductor chips

  • US 6,586,290 B1
  • Filed: 06/15/1998
  • Issued: 07/01/2003
  • Est. Priority Date: 11/30/1995
  • Status: Expired due to Term
First Claim
Patent Images

1. A method of making an ESD protection device in a semiconductor substrate, comprising:

  • forming in the substrate first and second heavily doped active areas as a source and a drain of a lateral CMOS transistor;

    forming in the substrate a third heavily doped area separated from the first active area;

    forming a first well resistor between and at least partially under the first active area and the heavily doped third area and conductively coupled thereto, the first well resistor having a higher sheet resistance than the first active area and the third area;

    forming in the substrate a first conductive layer disposed over the third area and electrically coupled thereto;

    forming in the substrate a fourth heavily doped area separated from the second active area;

    forming in the substrate a second well resistor formed between and at least partially under the second active area and the fourth heavily doped area and conductively coupled thereto, the second well resistor having a higher sheet resistance than the second active area and the fourth area; and

    forming in the substrate a second conductive layer disposed over the fourth area and conductively coupled thereto.

View all claims
  • 7 Assignments
Timeline View
Assignment View
    ×
    ×