Copper Wire Bonding Metal Bonding Pad Bonding In Depth Research

The development of electronic encapsulate technology, promote micro-chipinterconnect technology develop to lower cost and higher quality. The lower costadvantage of copper wire bonding will replace the gold wire bonding as mainstream.The difference attribute in copper and gold wire, the quality reduce by copper wire bonddeeply in pad metal. This article study reducing pad metal displacement in copper wirebond from bonding process and bonding factors。Base on wire bonding technology, a particular exposition and analysis of thecopper wire bonding were given. Compare the different between copper wire bondingand gold wire bonding. Experimental data measured by cross-section, standard theobservation and measurement method on pad metal displacement.Research on the materials science, the bond principle and mechanics as below list:1．In copper wire bonding process, analyze on search fore, bong fore, bond powerand process time. Design orthogonal experiment and find the trend between pad metaldisplacement and main parameters in wire bonding. The result show, bonding force andpower is prominent factor on pad metal displacement and get the pad metaldisplacement increase trend with bonding force and power. Optimize the mainparameters. Hold forth a new process to control pad metal displacement, it is strongbonding force and weak bonding power in copper wire bond.2．In bonding factors, discuss in the wire, capillary size, ultrasonic and free air ballto control pad metal displacement.Control pad metal displacement and avoid the copper bond puncture the pad metalinduce the destruction of the silicon substrate or circuit, the copper thin chip, multi-layerpad structure, low-K media and the active circuit (BOAC) on a chip applications.