E-ICP에 의한 산화막 식각특성

초록

The etch rate of SiO2 in E-ICP and CW-ICP system are investigated and the effect of addition gas (O2, H2) on SiO2 etch characteristics are compared. In all conditions, E-ICP shows better etch characteristics than CW-ICP. As the addition of small amount of O2 would increase F atom and O* concentration, E-ICP system shows highest etch rate (about 6000Å) at an optimized condition with 30% O2 in CF4 70Hz. The addition of H2 gas in CF4 plasma shows abrupt decrease in Si etch rate while it shows moderate decrease in SiO2 etch rate as expected.