On the surface stability of UV-cured InP-InGaAs HBTs using polyimide for passivation

摘要

The stability of UV-cured devices was studied concerning the transient effect. The experimental results indicate that the transient behavior suppressed by UV-irradiation could be re-activated during device operation if the device is operated with high power. The current transient re-activated during the device operation could be directly related to the device self-heating through thermal annealing effect - a significant increase PI trap density as well as the broadening of spatial electron trap distribution in PI annealed at high temperature. Properly design the device structure and layout with better thermal management to ensure a low junction temperature is necessary for PI-passivated InP HBTs.