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 120 GHz are described. Differential amplifiers are shown to have offset voltages with standard deviation below 2 mV and voltage gain as high as 200 per stage. Breakdown voltiages (BV/sub CB0/) above 20 V are demonstrated. Frequency dividers operating above 20 GHz are described.