High-Efficiency 250–320 GHz Power Amplifiers Using InP-based MOS-HEMTs

This study presents a broadband, high-efficiency power amplifier (PA) monolithic microwave integrated circuit (MMIC) that uses InP-based metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) with an extended drain-side access region and a broadband conjugate matching topology. Advanced device technologies such as double-side-doped structures, MOS gate structures, and asymmetric gate recess were adopted, and the length of the drain side access region was optimized to simultaneously obtain high power and efficiency. A common-source PA MMIC was fabricated, and an interstage circuit was designed to maximize the S21 per unit stage in the broadband, resulting in a record-high PAE and wide bandwidth.