RF frequency effects on molecular fragmentation

The chlorine contents of 40 kHz and 13.56 MHz RF silicontetrachloride and d ichlorosilane plasmas were investigated using actinometric evaluation in a parallel-plate (stainless-steel disk electrodes, stainless-steel reactor) e lectrode and in an electrodeless (external electrodes and glass reactor) di scharges, in the 50-500 W RF power and 100-500 mTorr pressure ranges. It wa s found that the frequency has a significant effect on the molecular fragme ntation of dichlorosilane and a less important effect on the fragmentation of silicontetrachloride. This behaviour was related to the molecular struct ures of the two starting components. The plasma-induced surface chemistries and morphology changes were also investigated and related to the different chemistries driven under 40 kHz and 13.56 MHz frequency environments. Plas ma-induced and frequency-controlled molecular fragmentation reactions can b e envisaged based on these findings.