HIGH-POWER-DENSITY AND HIGH-EFFICIENCY ATOMIC-PLANAR-DOPED ALGAAS INGAAS QUANTUM-WELL POWER HIGH-ELECTRON-MOBILITY TRANSISTORS FOR 2.4 V MEDIUM-POWER WIRELESS COMMUNICATION APPLICATIONS/

A high-power-density and high-efficiency molecular-beam-epitaxy-grown atomic-planar-doped AlGaAs/InGaAs quantum-well power high-electron-mob ility transistor (HEMT) was developed for low-voltage medium-power wir eless communication applications. The HEMT exhibited a maximum drain c urrent of 420 mA/mm and a maximum transconductance of 275 mS/mm. A two -dimensional electron gas with a high sheet charge density and a high electron mobility in the InGaAs quantum well contributed to the high c urrent density and high transconductance of the HEMT and enhanced the device power performance at low operating voltage. An output power den sity of 177 mW/mm and a power-added efficiency of 61% were achieved by the 2 mm HEMT at a drain voltage of 2.4 V and a frequency of 900 MHz. At 2.1 V drain voltage and 2.4 GHz, frequency, the device demonstrate d an output power of 24.4 dBm and a power-added efficiency of 57.4%. A n adjacent channel leakage power of -55 dBc was attained for the 1.9-G Hz pi/4-shifted quadrature phase shift keying modulation when the outp ut power was 22.2 dBm and the drain voltage was 2.4 V.