Direct Bonding of Copper with Aluminium Oxide

DBC substrate was tried to be prepared using a copper sample having a slot on one of its edge and alumina crucible. Both the materials were kept in a Muffle Furnace and are heated up to temperature range of 1025 C for about 7-8 hours under normal atmospheric conditions of the furnace. A very delicate bond was observed between the copper sample and alumina crucible when observed with the naked eye. Before taking the trial for bonding. the copper samples were cleaned using 10 % HCl solution and are pre oxidized in a muffle furnace at 350 C. SEM Analysis was conducted with pre oxidized copper samples to observe the thickness of the oxide layer and its texture on different copper samples oxidized for different time periods. The result was analyzed to infer the optimum thickness of oxide layer required for the formation of good bond.