ADVANCED HIGH POWER INP MILLIMETER-WAVE DEVICES AND CIRCUITS

SHORT GATE LENGTH GAAS BASED MESFETS AND MODULATION-DOPED FETS (MODFETS, OR HEMTS) HAVE DEMONSTRATED RESPECTABLE GAIN AND LOW NOISE FIGURE AT FREQUENCIES AS HIGH AS 94 GHZ; HOWEVER THEY CAN NOT PROVIDE HIGH POWER WITH HIGH ASSOCIATED EFFICIENCY. INP BASED LATTICE MATCHED MODULATION DOPED FETS, ON THE OTHER HAND, POSSESS A COMBINATION OF PROPERTIES INCLUDING HIGH THERMAL CONDUCTIVITY, HIGH SATURATED ELECTRON VELOCITY, AND POTENTIAL HIGH BREAKDOWN VOLTAGE WHICH WILL ALLOW TRULY SPECTACULAR PERFORMANCE FOR MILLIMETER-WAVE POWER APPLICATIONS. PRELIMINARY MEASUREMENTS OF ONE MICRON GATE TEST DEVICES INCORPORATING THIS MATERIALS STRUCTURE HAVE ALREADY DEMONSTRATED A TRANSCONDUCTANCE OF 410 MS/MM AND A CURRENT DENSITY OF 500 MA/MM. A RELATED INP BASED HETEROSTRUCTURE HAS ALSO DEMONSTRATED A GATE-SOURCE BREAKDOWN VOLTAGE OF -12 VOLTS. MICROWAVE MONOLITHICS INCORPORATED AND ITS SUBCONTRACTOR, THE UNIVERSITY OF CALIFORNIA AT SAN DIEGO, THEREFORE PROPOSE TO FURTHER DEVELOP THIS MATERIALS AND DEVICE TECHNOLOGY AND APPLY IT TO THE DESIGN AND FABRICATION OF MILLIMETER-WAVE POWER CIRCUITS. A SUITABLE TEST STRUCTURE WILL BE DESIGNED, FABRICATED, AND CHARACTERIZED DURING PROGRAM PHASE I. MEASURED PERFORMANCE OF THIS DEVICE WILL THEN GUIDE THE DESIGN AND FABRICATION OF A TBD HIGH POWER MILLIMETER-WAVE TEST DEVICE/CIRCUIT (SUCH AS A 60 GHZ HIGH EFFICIENCY POWER AMPLIFIER) IN PROGRAM PHASE II. ANTICIPATED BENEFITS/POTENTIAL APPLICATIONS - THE PRIMARY APPLICATIONS OF THE PROPOSED HIGH EFFICIENCY MILLIMETER-WAVE POWER DEVICES AND CIRCUITS ARE EXPECTED TO BE IN THE AREAS OF INTER-SATELLITE LINKS AND MILLIMETER-WAVE IMAGING SYSTEMS, WHICH ARE EQUALLY IMPORTANT FOR MILITARY AND COMMERCIAL COMMUNICATIONS AND RESOURCE MONITORING/SURVEILLANCE REQUIREMENTS. SECURE SHORT RANGE COMMUNICATIONS SYSTEMS WILL ALSO BENEFIT FROM THESE COMPONENTS.