Optical spectroscopic study of mechanisms in CCl4 plasma etching of Si

Abstract

The emission of Si, SiCl, Cl, CIl' CCl, Cl + , and Cl i has been observed in a CC1 4 rf disc harge in the presence ofSi( 100) in a plasma etching system. Spectral intensities have been recorded over a wide range of process gas flow rates and rf powers. These data have been analyzed to show that (i) SiCl emission from the A state arises through chemiluminescent reactions of metastable (J S) Si and (ii) the species which leaves the Si surface in the etching process is SiCl", (x = 0, 1, or 2) rather than SiC1 3 or SiCI 4 • To arrive at these conclusions, detailed chemical models are examined and shown quantitatively to reproduce our observed variations of emission with flow and power.

Spectroscopic Studies of RF Discharge Plasma at Plasma-Chemical Etching of Gallium Nitride Epitaxial Structures

“…There are very little experimental data on the influence of the ion energy on the evolution of spectra emitted by plasma in the tetrachloromethane atmosphere, and we did not manage to find them in available sources. From the available body of information, it follows that the major components observed in the emission spectra and mass spectrograms are CN, C 2 [4,7], Cl, Cl 2 , Cl + [4,8], C + 2 , C + , Cl + 2 , CCl 3 , CCl + 2 , CCl + , and so forth [4,9]. Therefore, the optimization of the plasma-chemical etching of GaN and the spectroscopic researches of plasma remain to be a challenging task nowadays.…”