Methods of forming staircase structures
US10147638B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 2017 |
| Grant date | Dec 4, 2018 |
| Priority date | — |
| Expiry date | Dec 29, 2037 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B41/27
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of forming staircase structures. The method comprises forming a patterned hardmask over tiers. An exposed portion of an uppermost tier is removed to form an uppermost stair. A first liner material is formed over the patterned hardmask and the uppermost tier, and a portion of the first liner material is removed to form a first liner and expose an underlying tier. An exposed portion of the underlying tier is removed to form an underlying stair in the underlying tier. A second liner material is formed over the patterned hardmask, the first liner, and the second liner. A portion of the second liner material is removed to form a second liner and expose another underlying tier. An exposed portion of the another underlying tier is removed to form another underlying stair. The patterned hardmask is removed. Staircase structures and semiconductor device structure are also disclosed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.