Heterojunction Bipolar Transistors for Microwave and Millimeter-Wave Integrated Circuits

This paper reviews the present status of GaAIAs/ GaAs HBT technology and projects the impact of these devices on microwave and millimeter-wave integrated circuits. Devices with f/sub max/ above 100 GHz are described. Differential amplifiers are shown to have offset voltages with standard deviation below 2 mV and voltage gain of 200 per stage. Breakdown voltages (BV/sub CBO/) above 20 V are demonstrated. Frequency dividers operating above 20 GHz are described.