4H-SiC Bipolar Transistors with UHF and L-Band Operation
We report for the first time on RF SiC BJTs fabricated on semi-insulating (SI) substrates with L-band performance. Small-periphery (4x150μm) devices were tested using on-wafer load-pull measurements up to 1.5GHz. Under pulsed conditions, the devices exhibited 10dB of power gain at 1GHz and a peak power density of 2.3W/mm (1.4W) with a 100μs pulse width and a 1% duty cycle. The power gain decreased to 8dB at 1GHz under CW conditions at a power density of 1.6W/mm (1W). The load-pull measurements were performed up to 125oC, which resulted in a 1 dB reduction of power gain compared to the room temperature performance. Results at 0.5 and 1.5 GHz are presented as well.
Robert P. Devaty, David J. Larkin and Stephen E. Saddow
I. Perez-Wurfl et al., "4H-SiC Bipolar Transistors with UHF and L-Band Operation", Materials Science Forum, Vols. 527-529, pp. 1421-1424, 2006