Study of defect engineering in the initial stage of SIMOX processing

Defect engineering for SiO2 precipitation was investigated during ion beam synthesis in the first stage of SIMOX processing. Vacancy defects were created in Si: (i) by a buried nanocavity layer pre-fabricated by He implantation and annealing and (ii) by excess vacancy generation during oxide synthesis induced by an additional simultaneous high-energy Si implantation.A narrow nanocavity layer was found to be an excellent nucleation site that effectively assists SiO2 formation. Such cavity layer must be adjusted to the excess vacancy profile of the O implant. The excess vacancy generation by simultaneous dual implantation avoids defect formation in Si. However, it is inappropriate to form a narrow oxide layer due to the too broad distribution of excess vacancies.