Hard Mask 용 SiO 2 의 NF 3 /Ar ICP 식각특성과 실험계획법과의 비교

Hard mask was widely used as etch mask due to the thermal instability of photo-resist in the etch pro- cess. The patterning process of hard mask must be guaranteed before everything else in order to accomplish the fine pattern transfer. The SiO 2 film as the hard mask was etched in the NF 3/Ar inductively coupled plasmas. Etch char- acteristics of the SiO 2 film as a function of the processing parameters were investigated. The best etch characteristics without deformation of photo-resist were obtained at 600 W ICP source power and 75 W RF chuck power, and the etch rate was 590 nm/min. The optimum etch conditions of the SiO 2 film by response surface method were 600 W ICP source power, 75 W RF chuck power, 55% NF3 concentration, and 20 mTorr operating pressure. Etch rate was 564 nm/min at the optimum etch conditions and was in good agreement within 4% error compared with the etch rate obtained by the experiment.