A study on the suppression of etch residues by O-2 gas addition in dry etching of Pt film

The properties of platinum etching were investigated using inductively coup led plasmas. However, problems such as low selectivity to oxide as an etchi ng mask, low etch dope and the etch residues remaining on the pattern sidew all were presented. In this paper, the etching by O-2/Cl-2/Ar gas mixture w as examined, And the residue-free surface and higher etch slope was observe d through transmission electron microscope (TEM) and scanning electron micr oscopy (SEM). The selectivity to oxide as an etching mask increased without having to decrease the etch rate in 5 % additive O-2 gas. In order to inve stigate the residue composition, X-ray photoelectron spectroscopy (XPS) ana lysis was used. XPS surface analysis proved that even a little O-2 gas can remove the Pt-Cl compounds as residues on the etched surface.