Reliability of InP-based HBT IC technology for high-speed, low-power applications

We report on the reliability of an InP-based AlInAs/GaInAs heterojunction bipolar transistor technology which has applications in very high-speed and low power integrated circuits. We have performed extensive accelerated lifetest experiments under different dc bias conditions and different ambient temperatures. For high-performance devices we predict meantime-to-failures in excess of 10⁷ hours at 125°C junction temperatures. We have also investigated the effects of hydrogen on HBT device characteristics which is particularly important for integrated circuits in hermetically sealed packages. We show that the transistor performance is not sensitive to a 4% hydrogen ambient. For integrated circuits requiring precision thin-film resistors we performed lifetest experiments on tantalum-nitride resistors used in our IC process. We show that these thin-film resistors are very stable and exhibit mean-time-to-failures exceeding that of discrete transistors