Can GaAs ICs achieve Si VLSI reliability?

The authors compare and contrast the failure modes in GaAs and Si IC technology, assess the demonstrated levels of reliability achieved in these technologies, and compare the distinct challenges facing the GaAs and Si communities as they attempt to quality chips of increasing complexity. It is concluded that there appears to be no fundamental property of GaAs limiting its reliability to be less than that offered by Si technology for present or future technology levels. Each technology has thus far met the challenge of increasing the device and interconnect component lifetimes to maintain or improve overall chip reliability. The future reliability challenges for both technologies will be in heat management and in the interconnect and contacts, which may be slightly more difficult for GaAs; the thermal conductivity of GaAs is only approximately 1/4 that of Si and the ohmic contacts of GaAs have traditionally been an area of concern. The future reliability challenges of the gate oxide in Si technology will require a continued reduction in supply voltage and continued large effort to improve gate insulator quality and device design.<>