Publications

Improved manufacturability of AlGaAs/GaAs Pnp heterojunction bipolar transistors

Clevenger, J.B.; Patrizi, G.A.; Peterson, T.C.; Cich, M.J.; Baca, A.G.; Klem, John F.; Plut, Thomas A.; Fortune, T.R.; Hightower, M.S.; Torres, D.; Hawkins, Samuel D.; Sullivan, Charles T.

Specially designed Pnp heterojunction bipolar transistors (HBT's) in the AlGaAs/GaAs material system can offer improved radiation response over commercially-available silicon bipolar junction transistors (BJT's). To be a viable alternative to the silicon Pnp BJT, improvements to the manufacturability of the HBT were required. Utilization of a Pd/Ge/Au non-spiking ohmic contact to the base and implementation of a PECVD silicon nitride hard mask for wet etch control were the primary developments that led to a more reliable fabrication process. The implementation of the silicon nitride hard mask and the subsequent process improvements increased the average electrical yield from 43% to 90%. © The Electrochemical Society.