MTJ CD variation by HM trimming
US11800811B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2021 |
| Grant date | Oct 24, 2023 |
| Priority date | — |
| Expiry date | Nov 8, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10N50/80
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A MTJ stack is deposited on a bottom electrode. A metal hard mask is deposited on the MTJ stack and a dielectric mask is deposited on the metal hard mask. A photoresist pattern is formed on the dielectric mask, having a critical dimension of more than about 65 nm. The dielectric and metal hard masks are etched wherein the photoresist pattern is removed. The dielectric and metal hard masks are trimmed to reduce their critical dimension to 10-60 nm and to reduce sidewall surface roughness. The dielectric and metal hard masks and the MTJ stack are etched wherein the dielectric mask is removed and a MTJ device is formed having a small critical dimension of 10-60 nm, and having further reduced sidewall surface roughness.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.