Trench transformation technology using hydrogen annealing for realizing highly reliable device structure with thin dielectric films

The shape and the surface morphology of the trench structure was successfully transformed by the annealing in hydrogen ambient. The corner was rounded and the surface morphology was smoothened on the inside of the trench. Electrical characteristics of the thin oxide grown in the deep trench capacitor were drastically improved. The hydrogen annealing condition was optimized based on the transformation mechanism.