Accurate electrical measurements for in situ diagnosis of RF discharges in plasma CVD processes

✍ Scribed by G. Viera; J. Costa; F.J. Compte; E. Garćı́a-Sanz; J.L. Andújar; E. Bertran

• Book ID: 104266251
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 135 KB
• Volume: 53
• Category: Article
• ISSN: 0042-207X
• DOI: 10.1016/s0042-207x(98)00410-2

✦ Synopsis

The electrical characterisation of radio-frequency (rf ) discharges lead to a better understanding of the plasma processes, since their electrical properties are directly related to microscopic discharge properties. In this paper, we present a new method to obtain, simultaneously, discharge complex impedance, dissipated rf power and self-DC voltage, using a non-perturbative system for the electrical measurements and a rapid, self-consistent mathematical algorithm. The measurement system provides two operation modes: (a) a real time mode, for monitoring the discharge electrical parameters during a plasma process and (b) a fast acquisition mode, with a time resolution to the microsecond, to study the time evolution of the discharge electrical parameters during transient phenomena.

Results for rf discharges in Ar and in SiH are presented. The electrical measurements were obtained from a wide range of gas pressures (1-100 Pa) and rf powers (10-300 W). The evolution of discharge complex impedance and dissipated rf power are discussed in terms of their relation to discharge physical phenomena.