Investigation of plasma-induced damage in silicon trench etching

In this study, we investigated the plasma-induced damage in silicon trench etching. The damage was measured by detecting the dark current, which was a very small leakage current thermally generated from silicon crystal defects. The results indicated that both the amount and depth of the sidewall damage in the trenches were almost the same as those of the bottom damage. From the results of analysis and simulation, we considered that the crystal defects inducing isotropic damage were mainly formed by hydrogen ions diffusing in the silicon trenches.