THE BEHAVIORS OF N AND NN_(i) TRAPS IN Gap UNDER PRESSURE: A THEORITICAL STUDY BASED ON EPM BAND STRUCTURE

We studied the pressure dependence of N and NNi traps in GaP based on EPM band structure.In calculation of Green's function,we used an approximate method combining with the special points method and the effective mass description of the band valleys.The results are in good agreement with the experiments only when proper changes of the effective masses under pressure are taken into account.