| 摘要 |
1309990 Welding by pressure HITACHI Ltd 19 April 1971 [2 March 1970] 22539/71 Heading B3R In ultrasonically bonding an electrode terminal on a semi-conductor body to a conductive lead, a metal layer is applied to the surface of the body opposite the terminal carrying surface, a vibration applying element is pressed into the metal layer, which is softer than the element, the element having at least one groove interrupting a working surface thereof which has a flat surface portion or portions adjacent the groove or grooves, and ultrasonic energy is applied to the element. The element has a hole 5 therein for connection to a vacuum to hold the semiconductor device over conductive leads, the semi-conductor device having a layer of soft metal, e.g. aluminium, gold or solder and the parallel grooves 6 are provided in the flat working face. The grooves taper away from the face and may be 20 microns deep and 250 microns maximum width. The grooves in other embodiments are replaced by mutually perpendicular grooves, grooves in concentric circles, a single spiral groove or radially arranged grooves. The linear grooves may be formed by grinding and the non-linear by electrical discharge machining and the element may be of tungsten carbide, titanium carbide or stainless steel. |
