Non-critical complementary masking method for poly-1 definition in flash memory device fabrication
US7307002B2 · kind B2 · utility
3Cited by
2References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2005 |
| Grant date | Dec 11, 2007 |
| Priority date | — |
| Expiry date | Jan 16, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B43/30
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for the definition of the poly-1 layer in a semiconductor wafer. A non-critical mask is used to recess field oxides in the periphery prior to poly-1 deposition by an amount equal to the final poly-1 thickness. A complimentary non-critical mask is used to permit CMP of the core to expose the tops of core oxide mesas from the shallow isolation trenches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.