DC9, LF dispersion and HF characterisation of short-time stressed inp based LM-HEMTS
InP based LM-HEMTs are stressed at room temperature in a minute time-frame. Depending on the applied DC bias, various failure mechanisms are favorised. Their influence on the device characteristics is measured and analysed. A significant change in the DC and HF parameters has been noticed when stressed in the impact ionization region, which is not recoverable. However, after stress in the avalanche region only the gate leakage current increased and this is recoverable after a few minutes. During stress in both regions, the gate current I/sub gs/ and the drain current I/sub ds/ vary on a logaritmic time scale. This enlightens the importance of possible influence of standard on-wafer DC and HF characterizations on the device perfon-nance.