MMICs in the millimeter-wave regime

Millimeter-wave monolithic microwave integrated circuits (MMICs) have been used in military and astronomy systems for many years, and, in the last ten years, commercial applications have been developed--in communications and automotive radar, for example. The recent evolution of integrated circuit (IC) technologies has improved the performance of silicon-based MMICs to over 100 GHz, even in standard bulk complementary metal oxide semiconductor (CMOS) processes. We believe that this will have a major impact in the future development of millimeter-wave systems, particularly since low-cost mass production has the potential to rapidly push the technology forward. In order to simplify the assembly and reduce cost, people have proposed the concept of system in package (SIP). Although there have been reports of millimeter-wave integrated transceivers [1]-[22], direct integration of baseband circuitry on the same millimeter-wave transceiver chip has not been found in the literature to date. Current millimeter-wave single-chip transceivers integrate transmit/receive function blocks, potentially including the power amplifier (PA), local oscillator (LO), and antenna together. Most such millimeter-wave transmit/receive MMICs were fabricated in GaAs technologies in the past [1]-[6], [19]-[21]; however, siliconbased( CMOS, silicon germanium heterojunction bipolar transistor (SiGe HBT) or BiCMOS) single-chip transmit/receive MMICs have been reported in the last two to three years [7]-[18], [22]. In this article, the current status of compound semiconductor and silicon-based millimeter-wave MMICs will be reviewed, and the future trends in millimeter-wave system on chip (SOC) will be discussed. The issues of millimeter-wave SOC and SIP will also be addressed.