Showerhead with reduced backside plasma ignition
US10745807B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 2019 |
| Grant date | Aug 18, 2020 |
| Priority date | — |
| Expiry date | May 21, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/3244
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Embodiments of the present disclosure relate to a showerhead assembly for use in a processing chamber. The showerhead assembly includes a porous insert disposed in a space defined between a gas distribution plate and a base plate to moderate the corrosive radicals resulting from plasma ignition to reduce particle issues and metal contamination in the chamber. The porous insert is a conductive material, such as metal, used to reduce the gap electrical field strength, or may be a dielectric material such as ceramic, polytetrafluoroethylene, polyamide-imide, or other materials with a low dielectric loss and high electrical field strength under conditions of high frequency and strong electric fields. As such, the electrical breakdown threshold is enhanced. The porous insert may reduce and/or eliminate showerhead backside plasma ignition and may include multiple concentric narrow rings that cover gas holes of the gas distribution plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.