High gain, high efficiency, low voltage, medium power Si-bipolar transistor suitable for integration

Medium power transistors in a high performance double polysilicon bipolar process have been fabricated. On-wafer loadpull measurements show high gain (15 dB) and high maximum efficiency (60%) at 1.8 GHz with 27 dBm of output power. These results were obtained with a low supply voltage of 3.5 V. More importantly, these results were obtained with transistors with a buried layer having a collector contact at the top, which makes it possible to integrate power amplifiers on chip.