High selectivity and low stress carbon hardmask by pulsed low frequency RF power
US9589799B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2014 |
| Grant date | Mar 7, 2017 |
| Priority date | — |
| Expiry date | Jul 18, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02274
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of forming high etch selectivity, low stress ashable hard masks using plasma enhanced chemical vapor deposition are provided. In certain embodiments, the methods involve pulsing low frequency radio frequency power while keeping high frequency radio frequency power constant during deposition of the ashable hard mask using a dual radio frequency plasma source. According to various embodiments, the low frequency radio frequency power can be pulsed between non-zero levels or by switching the power on and off. The resulting deposited highly selective ashable hard mask may have decreased stress due to one or more factors including decreased ion and atom impinging on the ashable hard mask and lower levels of hydrogen trapped in the ashable hard mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.