No abstract

No abstract

AIGaAs/GaAs HBTs with collector launcher structure are developed for the low operation voltage power amplifier. We discuss the relationship between the HBT collector structure and its microwave power performance, demonstrating that the launcher structure suppresses the Kirk effect near the saturation region and increases the current handling capability. A fabricated HBT, which has an emitter size of 2 pm x 20 pm x 32 fingers, exhibits a power added efficiency , qadd , of 70% with an output power, Pout, of 30 dBm and a power gain, Ga, of 15.7dB at a supply voltage of 3.5 V and a frequency of 900 MHz. At 2.5 V, Pout is 26.5 dBm, qadd is 70% and Ga is 14.7dB. These results demonstrate that HBTs with a collector launcher structure are appropriate for power applications, especially at low voltage operation.

No abstract

No abstract