화학공학소재연구정보센터
Journal of Vacuum Science & Technology A, Vol.17, No.5, 2546-2550, 1999
Very uniform and high aspect ratio anisotropy SiO2 etching process in magnetic neutral loop discharge plasma
Magnetic neutral loop discharge (NLD) plasma is a new type for dry etching process characterized dy effective coupling of the input electric field electron electron motion near the magnetic neutral loop (NL) region. Therefore, dense plasma can be produced and controlled spatially by changing the position of the NL. Uniformity was controlled by changing the radius of NL temporally during the etching using a repetition frequency of 0.1 Hz, so that the deviation of the SiO2 etch rate was within 2% (3 sigma) on 200-mm-diam wafer. In nanoscale pattern etching processes, we found that CHF2+ ions played an important role in very high aspect ratio profile etching. In CHF2+ ion-rich plasma, ZEP photoresist patterned 20 nm space was successfully etched 800 nm in depth at the pressure of about 0.3 Pa, using CH2F2, C4F8, and O-2.