| Abstract: | The study on the instability of gate contacts of Al/Ni gate AlGaAs/GaAs HEMT's was performed by means of storage tests carried out at three different temperatures: 200°C, 240°C and 300°C. Data from tests as long as 5000 hours were analyzed. At the highest temperature the main failure mode was the reaction between the Al of the gate electrode and the Au of the metallization. At 200°C, 240°C an increase of the barrier height was detected. The activation energy determined and the comparison with the data existing in literature is reported. |
