Abnormal characteristics of etched profile on thick dielectrics for MEMS in inductively coupled plasma

Abstract

We present a study that shows the independent influence of abnormal ion trajectories in the etched hole profile on thick dielectrics used in micro-electro mechanical system (MEMS) fabrication under fluorocarbon plasma. Under fixed neutral and ion fluxes, a simple dielectric block located on the chuck electrode can control the plasma molding effect, thus creating non-symmetric incidence ion angles. Changes in nanoscale etching profiles with variations in the plasma molding effect were obtained to investigate the quantitative effects of abnormal incidence ion angles under fixed plasma conditions. We found no significant changes in abnormal etching behavior with variation in the size of the nanoscale hole. We believe that this approach will be an effective method to support quantitative data of predictive modeling for the better understanding of abnormal plasma etching behavior in nanoscale device fabrications.