New screened plasma-enhanced atomic vapor deposition to improve trench covering ability of SbTe films

In this paper, a new screened plasma-enhanced atomic vapor deposition technique was studied for increasing trench covering ability of Sb-Te phase change film. Trench-structure cells of phase change random access memory can lower thermal energy loss and thermal cross-talk among adjacent memory cells. Using a plasma sheath effect with metallic mesh inside a reaction chamber, a step coverage was greatly increased in various experimental conditions. With consideration of a model of the plasma sheath, the trench covering ability of the films was evaluated and we expect this research to provide a new deposition method for the fine control of step coverage.