| 摘要 |
PURPOSE:To prevent incomplete wire bonding to bonding pads and electrodes on a substrate by mounting a semiconductor pellet on the substrate with silver paste and baking it under subatomospheric pressure. CONSTITUTION:A substrate S where a pellet P is mounted by using silver paste is put in a high-temperature tank; the inside of the high-temperature tank is evacuated to a pressure of lower than the atmospheric pressure, e.g. 0.1-0.2 atm. Then, the inside of the high-temperature tank is heated at 100-150 deg.C by keeping the reduced pressure. After this temperature has been kept for 1-2 hours, the inside of the high-temperature tank is kept leaked and is then returned to the atmospheric pressure. Then, the substrate S where the pellet P is mounted firmly with the baked silver paste is taken out from the high- temperature tank. By this method, the inside of the high-temperature tank is never filled with an out-gas which is generated during the baking process of the silver paste. As a result, the out-gas of the silver paste does not adhere to the surface of the semi-conductor pellet and to an electrode part on the substrate; the defective adhesion of a bonding pad part and the electrode on the substrate to a bonding wire is eliminated.
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