Patent · US Active

Method for forming stair-step structures

US9275872B2 · kind B2 · utility

3Cited by
20References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 2014
Grant dateMar 1, 2016
Priority date
Expiry dateDec 23, 2034

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B41/27
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for forming a stair-step structure in a substrate is provided. An organic mask is formed over the substrate. A hardmask with a top layer and sidewall layer is formed over the organic mask. The sidewall layer of the hard mask is removed while leaving the top layer of the hardmask. The organic mask is trimmed. The substrate is etched. The forming the hardmask, removing the sidewall layer, trimming the organic mask, and etching the substrate are repeated a plurality of times.

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