Reliability of 70 nm metamorphic HEMTs

The reliability and degradation mechanisms of 70 nm gate length metamorphic InAlAs/InGaAs HEMTs for low noise applications will be presented and discussed. Based an a 10% g(ind m max) failure criterion, a median time to failure of 10(exp 6) h and an activation energy of 1.3 eV in air were found. By comparing the electrical device characteristics before and after stress, gate sinking, ohmic contact degradation, and hot electron degradation were found to be the major failure mechanisms. The stress induced platinum diffusion into the semiconductor was quantified by cross-section TEM.