Nozomu Okumura

Fluxless solder joining using alkane

Abstract Electronics products are becoming smaller these days. Thus the technology to connect fine pitch electrodes is very important. We developed a new soldering method without applying any flux, which deteriorates the insulation property between electrodes. In the ordinary soldering method, flux is used to dissolve the oxide film. In the new method, we have introduced alkane to remove oxide film by physical reaction. When heat is applied and alkane is boiled, volume expansion energy breaks the oxide film and the desirable clean solder surface is obtained. As a result, the connections become as strong as using the ordinary method.