CF3, CF2 AND CF RADICAL MEASUREMENTS IN RF CHF3 ETCHING PLASMA USING INFRARED DIODE-LASER ABSORPTION-SPECTROSCOPY

We have measured the characteristics of CF3, CF2 and CF radical densities in RF CHF3 etching plasma under the same condition using infrared diode laser absorption spectroscopy, for the first time. The CFx radical density measurements have been performed as a function of input RF power, CHF3 gas pressure and distance from the RF electrode. On the basis of these systematic measurements, the generation and loss processes of CFx radicals in RF CHF3 plasma were discussed.