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

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-O2. 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.