Failure Analysis on Damaged GaAs HEMT MMIC Caused by Microwave Pulse

Failure examination is carried out by a scanning electron microscope on gallium arsenide (GaAs) high electron mobility transistor (HEMT) monolithic microwave integrated circuit damaged with microwave pulses. The examination results show that there are four types of defects in ten damaged chips. Among the previous types, one type of defect occurred in most damaged chips was examined, namely the planar spiral inductor between the output terminal of the last-stage HEMT and dc power supply is burned out. Specific to this type of defect, combining with the conductor loss theory and heat formula, the mechanism of heating and melting exerted on the planar spiral inductor of the chip under the action of microwave pulses is analyzed in this paper. The input power required for reaching Au and Cu microstrip melting point is computed.