Reliability of Microwave Gallium Arsenide Field Effect Transistors

It has been demonstrated that failures of gallium arsenide field effect transistors often occur at the sites of minor manufacturing defects. SEN and optical examination can be used to reject devices with such defects. Failure may often be traced to energy pulses which cause expulsion of material from localized areas. Failures caused by positive and negative pulses have distinctive characteristics: positive pulses on the gates tend to cause failures close to the gate bonding pads, or at regions of high gate resistance; negative pulses tend to cause failures at manufacturing defects. The damage may not cause the devices to go out of electrical specification but will seriously reduce their expected life.