THERMAL MANAGEMENT FOR HIGH-DENSITY ELECTRONICS USING EPITAXIAL LIFTOFF TECHNOLOGY

WE PROPOSE TO USE EPITAXIAL LIGTOFF TECHNOLOGY TO REMOVE SEMICONDUTRO LAYERS WHICH ARE ONLY A FEW MICROMETERS THICK FROM THE ORIGINAL SUBSTRATE. THE REMOVED LAYERS CAN THEN BE TRANSFERRED TO A HEAT CONDUCTING MATERIAL WHICH IS ALSO A GOOD ELECTRICAL INSULATOR. THIS TYPE OF STRUCTURE MAXIMIZES THE THERMAL CONDUCTIVITY BETWEEN THE DEVICE LAYERS AND SUBSTRATE. THIS TYPE OF STRUCTURE CAN ALSO FACILITATE THREE-DIMENSIONAL INTEGRATION BY ALLOWING TH EDEVICE LAYERS OF SEMICONUDSTRO MATERIAL, SPEARATED BY ELECTRICALLY INUSLATING LAYERS TO BE STACKED TOGETHER. IN PHASE I WE WILL DEMONSTRATE THE ABILITY TO TRANSFER LAYERS OF EPITAXIALLY GROWN MATERIAL TO A DIAMOND SUBSTRATE, WHERE THE HTEAT TRANSFER BETWWEEN THE SPITACIAL FILM AND THE SUBSTRATE WILL BE TESTED. WE WILL DEVELOP DESIGNS FOR ACTIVE AND PASSIVE HEAT DISSIPATION FROM BOTH TOW AND THREE-DIMENSIONAL STRUCTURES. WE WILL CONSIDER THREE DIFFERENT APPROACHES TO HEAT DISIPPATION FROM THE IMMEDIATE VICINITY OF THE DEVICE: 1) PASSIVE THERMAL SPREADING, 2) FORCED LIQUID COOLING, AND 3) INTEGRAL HEAT-PIPE COOLING. WE WILL CHOOSE ONE OF THE LATTER APPROACHES, AND WILL DESIGN A DEMONSTRATION SYSTEM TO BE FABRICATED IN PHASE II.