Optical emission spectroscopy analysis on the chemical reaction in etching of SrBi2Ta2O9 (SBT) thin films using inductively coupled Cl2/Ar plasma

The optical emission spectroscopy (OES) has been used as a diagnostic tool for analyzing chemical reactions in plasma etching. In this paper, since the research oil the etching of SrBi2Ta2O9 (SBT) thin film was few (specially cl(2)-base), we had studied inductively coupled plasma etching of the SBT thin film by means of OES. In our previous papers [1,2], it had been revealed that SBT thin films etched more effectively by chemically assisted reactive ion etching. The small addition Of Cl-2 gas into Ar plasma enhances the etch rate of SBT. The etch rate of SBT thin films depends on the concentration of Ar ion density. These results were confirmed by XPS analysis. The OES results suggest chemical reaction model of between etchants and compositions of thin films in the plasma.