Patent · US Active

Stair step formation using at least two masks

US9082772B2 · kind B2 · utility

7Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 20, 2013
Grant dateJul 14, 2015
Priority date
Expiry dateNov 20, 2033

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/0002
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Apparatuses and methods for stair step formation using at least two masks, such as in a memory device, are provided. One example method can include forming a first mask over a conductive material to define a first exposed area, and forming a second mask over a portion of the first exposed area to define a second exposed area, the second exposed area is less than the first exposed area. Conductive material is removed from the second exposed area. An initial first dimension of the second mask is less than a first dimension of the first exposed area and an initial second dimension of the second mask is at least a second dimension of the first exposed area plus a distance equal to a difference between the initial first dimension of the second mask and a final first dimension of the second mask after a stair step structure is formed.

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