THz MMICs based on InP HBT Technology

An indium-phosphide (InP) double-heterojunction bipolar transistor (DHBT) based suite of terahertz monolithic integrated circuits (TMICs) fabricated using 256 nm InP DHBT transistors and a multipurpose three metal layer interconnect system is reported. The InP DHBT MMIC process is well suited for TMICs due to its high bandwidth (fmax = 808 GHz) and high breakdown voltage (BVCBo = 4V) and integrated 10-μm thick layer of BCB dielectric supporting both low-loss THz microstrip lines for LNA, PA, and VCO tuning networks, and high-density thin-film interconnects for compact digital and analog blocks. TMIC low noise and driver amplifiers, fixed and voltage controlled oscillators, dynamic frequency dividers, and double-balanced Gilbert cell mixers have been designed and fabricated. These results demonstrate the capability of 256 nm InP DHBT technology to enable sophisticated single-chip heterodyne receivers and exciters for operation at THz frequencies.