Method for forming stair-step structures
US8535549B2 · kind B2 · utility
3Cited by
7References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 19, 2011 |
| Grant date | Sep 17, 2013 |
| Priority date | — |
| Expiry date | Dec 5, 2031 |
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 hardmask is removed. 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.