Advanced performance of small-scaled InGaP/GaAs HBT's with f/sub T/ over 150 GHz and f/sub max/ over 250 GHz

We have achieved advanced high-frequency performance in small-scaled InGaP/GaAs HBT's due to the further reduction of the parasitic capacitance by refining the device design and the process technology. An f/sub T/ of 156 GHz and an f/sub max/ of 255 GHz were achieved for an HBT with an emitter size S/sub E/ of 0.5/spl times/4.5 1/spl mu/m/sup 2/ at a collector current I/sub C/ of 3.5 mA. A 1/8 static frequency divider using these HBT's operated at a maximum toggle frequency of 39.5 GHz.