High density plasma tool with adjustable uniformity and stochastic electron heating for reduced gas cracking
US6262538A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 26, 1999 |
| Grant date | Jul 17, 2001 |
| Priority date | — |
| Expiry date | Aug 26, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/32082
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
VHF/UHF power having a frequency of about 40 MHz or higher is applied across generally radial elements of an antenna and the phase of a standing wave component of the voltage in the generally radial elements is adjusted to provide relatively uniform density of a high density plasma across an area of at least the size of a semiconductor wafer being processed. Capacitive coupling of power to the plasma enhances the hot tail distribution of electron energies which is associated with low levels of gas cracking and the production of radicals such as fluorine which are not material-selective in semiconductor processing operations such as oxide etching. Accordingly, material-selectivity of processes may be maintained while the high density plasma accelerates the process to significantly improve tool throughput.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.