Si/Au/Ni alloyed ohmic contact to n-GaAs and fabricating process therefor

摘要

An improved alloyed ohmic contact to n-type GaAs is provided utilizing a Si-based metallization of Si/Au/Ni and exhibiting low contact resistivity and high thermal stability. An improved process for fabricating the inventive contact is also provided comprising the step of first depositing the Si film on the GaAs substrate, thereby simplifying the fabrication of monolithically integrated devices, particularly advanced electro-optic devices, by incorporating self-aligned Si-based contacts in the process. A further improvement is provided in the use of a lift-off-defined Si layer as a reactive-ion etch mask to serve as the self-aligned contact in the process, thereby eliminating a critical photolithographic step of aligning the contact metallization.