Reliability of passivated 0.15 /spl mu/m InAlAs-InGaAs HEMTs with pseudomorphic channel

Accelerated life tests of 0.15 /spl mu/m gate length InAlAs-InGaAs HEMTs were performed under DC electrical stress at four temperatures in nitrogen. By defining a 10% transconductance degradation as the failure criterion, we found an activation energy of 1.8 eV and a projected lifetime of 5/spl times/10/sup 6/ hrs at 125/spl deg/ ambient temperature. The degradation was found to be much faster in air than in nitrogen. High temperature storage tests showed that our devices are not sensitive to hydrogen.