Methods and systems for independent control of radical density, ion density, and ion energy in pulsed plasma semiconductor device fabrication
US9767991B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 4, 2015 |
| Grant date | Sep 19, 2017 |
| Priority date | — |
| Expiry date | Nov 4, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/334
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
For a first period of time, a higher radiofrequency power is applied to generate a plasma in exposure to a substrate, while applying low bias voltage at the substrate level. For a second period of time, a lower radiofrequency power is applied to generate the plasma, while applying high bias voltage at the substrate level. The first and second periods of time are repeated in an alternating and successive manner for an overall period of time necessary to produce a desired effect on the substrate. In some embodiments, the first period of time is shorter than the second period of time such that on a time-averaged basis the plasma has a greater ion density than radical density. In some embodiments, the first period of time is greater than the second period of time such that on a time-averaged basis the plasma has a lower ion density than radical density.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.