Implant and annealed ohmic contact to a thin quantum well

Abstract

We demonstrate for the first time that ion implantation and implant activation annealing, combined with a heavily doped InGaAs surface layer, can be used to make nonalloying shallow ohmic contact to an n-type InGaAs (or GaAs) quantum well. Quantum Hall effect and Shubnikov–de Haas oscillations are clearly observed, which indicates that electrons in the quantum well remain two dimensional despite the post-implantation high-temperature annealing. This technique can be applied to devices that would need to make shallow ohmic contact to a thin (∼100 Å or less) quantum well, where existing selective etching approaches fail to work.