Vertical-cavity surface-emitting lasers integrated onto silicon substrates by PdGe contacts

Abstract

Vertical-cavity surface-emitting lasers (VCSELs) have been integrated onto an aluminium coated silicon substrate. The InGaAs top-emitting VCSELs were grown by molecular beam epitaxy and individual lasers were defined by high energy proton implantation. The substrate was removed by a new substrate removal process and the lasers were bonded to an aluminised silicon substrate using a Pd/Ge/InSn contact. Threshold currents below 5.5 mA and output powers of ~1 mW were obtained for 40 µm VCSELs bonded to Si.