| 摘要 |
PURPOSE: To quickly form a flat film by containing magnesium or zinc with a specific concentration for quickening the migration of a semiconductor film from three-dimensional growth to two-dimensional growth. CONSTITUTION: In n-type nitride compound semiconductor crystal film where Si is added, the migration from three-dimensional growth to two-dimensional growth is slow. However, by adding magnesium simultaneously, the migration from the three-dimensional growth to the two-dimensional growth occurs relatively quickly, namely when the film thickness is thin. By adding magnesium, a flat thin film can be formed quickly. However, since magnesium is originally an impurity of acceptor property originally, its excessive addition prevents n-type crystal. The range of impurity concentration for achieving effect is 1×10<15> cm<-3> -1×10<17> cm<-3> in magnesium and 1×10<15> cm<-3> -1×10<17> cm<-3> in zinc. Buffer layer 22, n-type GaN layer 23, and n-type InGaN layer 24 are formed on Sapphire substrate 21. The addition of Zn helps a flat thin film to grow and a flat thin film can be formed quickly. |
