论文信息 - SiO2/Si selectivity in high density CHF3/CH4 plasmas: Role of the fluorocarbon layer

SiO2/Si selectivity in high density CHF3/CH4 plasmas: Role of the fluorocarbon layer

A new high density plasma SiO"2 etching process based on CHF"3/CH"4 mixture is investigated by means of plasma diagnostics and surface analysis. Selectivity as high as 15 with respect to silicon has been obtained. Besides, a slight decrease of the SiO"2 etch rate is observed as compared to CHF"3. Deposition of a carbon-rich fluorocarbon layer on the SiO"2 is thought to play an important role in the etching mechanism, as generally described for Si.

[1] Marc Schaepkens,et al. High density fluorocarbon etching of silicon in an inductively coupled plasma: Mechanism of etching through a thick steady state fluorocarbon layer , 1998 .

[2] Olivier Joubert,et al. Fluorocarbon high‐density plasmas. II. Silicon dioxide and silicon etching using CF4 and CHF3 , 1994 .

[3] Masaru Hori,et al. Fluorocarbon radicals and surface reactions in fluorocarbon high density etching plasma. II. H2 addition to electron cyclotron resonance plasma employing CHF3 , 1996 .