NANOMETER-SCALE SELF-ALIGNED GATE MILLIMETER-WAVE POWER DEVICES AND INTEGRATED CIRCUITS

MILLIMETER-WAVE TECHNOLOGY IS FINDING USE IN MANY COMMERCIAL APPLICATIONS INCLUDING COMMUNICATIONS, RESOURCE MONITORING, COLLISION-AVOIDANCE, AND SECURITY/SURVEILLANCE SYSTEMS. ESSENTIAL TO THESE APPLICATIONS IS EFFICIENT POWER GENERATION AT MILLIMETER-WAVE FREQUENCIES. PRESENT GAAS- AND INP-BASED MODULATION-DOPED FIELD EFFECT TRANSISTORS (MODFETS/HEMTS), IN SPITE OF GOOD SMALL SIGNAL GAIN AND LOW NOISE FIGURE AT 94 GHZ, ARE, HOWEVER, NOT SUITABLE FOR POWER APPLICATIONS. MAJOR DEFICIENCIES OF PRESENT "POWER" MODFETS INCLUDE LOW POWER GAIN AND BREAKDOWN VOLTAGE. A NANOMETER-SCALE SELF-ALIGNED GATE WITH SEPARATELY CONTROLLABLE GATE-SOURCE AND GATE-DRAIN SPACINGS WILL ENHANCE BOTH GATE-DRAIN BREAKDOWN AND POWER GAIN. RESEARCHERS ARE EXPLOITING THE ADVANCED NANOFABRICATION TECHNIQUE FOR HIGH PERFORMANCE MILLIMETER-WAVE POWER DEVICES, AND CONCURRENTLY USING THE NANOFABRICATED STRUCTURES TO STUDY CARRIER TRANSPORT PROPERTIES SUCH AS VELOCITY OVERSHOOT IN REALISTIC MATERIALS AND DEVICE SYSTEMS. THE COMBINATION OF NANOMETER-SCALE ASYMMETRIC SELF-ALIGNED GATES AND ADVANCED HETEROSTRUCTURE MATERIALS RESULTS IN HIGH-POWER, HIGH-GAIN MILLIMETER-WAVE DEVICES AND CIRCUITS. THE SCIENTIFIC KNOWLEDGE AND DATA GAINED BY THE STUDIES WILL ALSO BE VALUABLE TO THE DESIGN OF FUTURE GENERATION HIGH-FREQUENCY AND HIGH-SPEED COMPONENTS.