Patent · US Expired

Methods for the optimization of substrate etching in a plasma processing system

US7078350B2 · kind B2 · utility

7Cited by
3References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 2004
Grant dateJul 18, 2006
Priority date
Expiry dateSep 11, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/76813
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method of etching a substrate in a plasma processing system is disclosed. The substrate has a semi-conductor layer, a first barrier layer disposed above the semi-conductor layer, a low-k layer disposed above the first barrier layer, a third hard mask layer disposed above the low-k layer; a second hard mask layer disposed above the third hard mask layer, and a first hard mask layer disposed above the second hard mask layer. The method includes alternatively etching the substrate with a first etchant and a second etchant, wherein the first etchant has a low selectivity to a first hard mask material of the first hard mask layer, a third hard mask material of the a third hard mask layer, and a first barrier layer material of the first barrier layer, but a high selectivity to a second hard mask material of the second hard mask layer; and wherein the second etchant has a high selectivity to the first hard mask material of the first hard mask layer, the third hard mask material of the third hard mask layer, and the first barrier layer material of the first barrier layer, and the second etchant has a low selectivity to the second hard mask material of the second hard mask layer.

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