Applied Science and Convergence Technology 2002; 11(2): 113-118
Published online June 1, 2002
Copyright © The Korean Vacuum Society.
Philgu Jung,Wantae Lim,Guansik Cho,Minhyun Jeon,Jaeyoung Lim,Jewon Lee,Kuksan Jo
We developed engineering methods to control gas flow in a plasma reactor in order to achieve good etch depth uniformity for large area GaAs etching. Finite difference numerical method was found quite useful for simulation of gas flow distribution in the reactor for dry etching of GaAs. The experimental results in BCl₃/N₂/SF_6/He ICP plasmas confirmed that the simulated data fitted very well with real data. It is noticed that a focus ring could help improve both gas flow and etch uniformity for 150 ㎜ diameter GaAs plasma etch processing. The simulation results showed that optimization of clamp configuration could decrease gas flow uniformity as low as ± 1.5 % on an 100 ㎜(4 inch) GaAs wafer and ± 3 % for a 150 ㎜(6 inch) wafer with the fixed reactor and electrode, respectively. Comparison between simulated gas flow uniformity and real etch depth distribution data concluded that control of gas flow distribution in the chamber would be significantly important in order or achieve excellent dry etch uniformity of large area GaAs wafers.