PROJECT TITLE :

Lifetesting GaN HEMTs With Multiple Degradation Mechanisms

ABSTRACT:

A technique is described, to efficiently evaluate the reliability of an RF semiconductor device when several different mechanisms contribute simultaneously to its wearout. This can be of interest for gift-day GaN HEMT devices as a result of symptoms of several simultaneous degradation mechanisms are reported widely. The technique involves 1st finding DC parameters that are “signatures” of every mechanism. Then, separate DC-stress lifetests are performed to seek out the degradation rates for the signature parameters, at many temperatures, and the corresponding Arrhenius curves. Next, an RF-stress lifetest (with solely one stress condition) is performed, whereas monitoring all of the signature parameters and also the RF performance. This is often used to work out the “scaling factors” between the rates of modification in the DC lifetests and therefore the rates of modification in the RF application. Applying these scaling factors to the first Arrhenius curves provides an “overall” Arrhenius plot for the RF application with several different lines, for the various degradation mechanisms. The technique will be extended to further degradation mechanisms, by conducting additional DC and RF lifetests whereas monitoring applicable signature parameters.