A Main Factor Determining The Uniform Step Cverage in Chemical Vapor Deposition

摘要

Profile evolution simulations during chemical vapor deposition based on a 2-D continuum model reveal that the type of surface kinetics plays an important role as a measure of determining step coverage of ilms deposited in a high aspect ratio trench or via. The linear surface kinetics, resultign from adsorption rate limitation, is found to be difficult to bring about conformal step coverage in a deep narrow trench without reducing the growth rate considerably; that is, under such a condition void free filling can not be achievable with holding an appropriate growth rate. high tendency of the precursor for chemical equilibrium on a surface, tending to cause the non-linear surface kinetics by surface reaction limitation, is mainly responsible for the significant improvement of step coverage in TEOS-based depositions.