Sequential implantation)on characteristics and structures have been described by techniques of RBS and TEM. Especially the transition region of Si/SiO2 interface is emphatically studied. The results show that the sequentical implantation and annealing(compared with single implantation in the same implantation dose)can not only evidently improve the quality of top layer and buried layer of SIMOX
but also evidently reduce the width of Si/SiO2 interface transition region.