摘要

A new technique to monitor plasma processes is presented. An autocorrelated neural time series (A-NTS) network was used to model ion energy distribution (IED). The ion energy data were collected during a deposition of silicon nitride films in a SiH(4)-NH(3) inductively coupled plasma. A backpropagation neural network was used to build IED model. Prediction performance of A-NTS model was evaluated as a function of training tolerance as well as a detection sensitivity. The ANTS models demonstrated detection sensitivities high enough to detect plasma faults. Maximum sensitivity of A-NTS models obtained was more than 55% for all fault cases. Optimised A-NTS models yielded the prediction errors of 1.41 and 2.18% for 80 and 60% IED respectively. The presented technique can be applied to monitor any kinds of plasma faults and is expected effective particularly to those faults sensitive to ion bombardment variations.

  • 出版日期2010-4