Lifetime control in silicon through focused laser beam damage

Abstract : This report consists of two chapters. Chapter I discusses minority carrier lifetime degradation in silicon as a result of 200 Kev argon and 80 Kev silicon implantation. The lifetime degradation is studied for the implantation dose range of 10 to the 11th power to 10 to the 16th power ions/cm sq. The lifetime degradation is different for argon and silicon implantation. For low argon implantation the decrease in lifetime is impurity controlled. At a higher dose the decrease in lifetime is caused by the argon impurity and by the crystal defects generated by the recrystallization of the amorphous damage layer. For silicon implantations the decrease in lifetime is caused by crystal defects only and is minor up to a dose of 10 to the 14th power Si(+)/cm sq. Chapter II reports results on buried layer gettering through high energy oxygen and argon implantations. High energy argon gettering depends on the implantation dose. Maximum gettering is obtained for high dose implantation. Oxygen gettering shows no implantation dose dependency. Remarkable gettering efficiencies are obtained for an implentation dose of 10 to the 11th power 0(+)/cm sq.