Application of the Taguchi’s design of experiments to optimize a bromine chemistry-based etching recipe for deep silicon trenches

Abstract

In this article, the design of experiments (DOE) of the Taguchi method was used to optimize a deep silicon trench etching recipe in a commercial etcher, Lam Research TCP9400. A L9 orthogonal array was selected with four factors and three levels. The four factors included chamber pressure, bottom power, flow rate ratio of HBr to He, and flow rate of He–O 2. It was found that the chamber pressure has a stronger influence on the etching rate and taper angle of a trench and that the bottom power has a proportional effect on the taper angle of a trench.