Abstract: | N-type layers in GaAs with high free electron concentrations have been produced by multiple implantation of Ga, As, or P with
dopant species such as Se, Si, or Ge. The implants that have been investigated include Si, Si + P, Ge, Ge + As, Se, and Se
+ Ga. The multiple implants Si + P, Ge + As, and Se + Ga gave higher peak carrier concentrations, especially at lower anneal
temperatures, than did the respective single implants Si, Ge, and Se. In fact, Ge when implanted alone produced a p-type layer
while the Ge + As multiple implant produced an n-type layer. Multiple implants with Si and Ge as dopants showed significant
thermal diffusion during the anneal. Multiple implants of Ga with Se, on the other hand, resulted in reduced thermal diffusion
in comparison with single Se implants. |