Crystallizing metal compound film on plastics by plasma-based ion implantation

It has been difficult to sputter-deposit crystalline compound directly on a substrate of low heat-resistant material like polymer. In this study a new apparatus is developed which deposits metallic compound film in crystalline structure directly on a substrate at lower temperature than 200°C (473K). The apparatus consists of a magnetron-sputtering deposition system with multi targets as well as of an ion irradiation system which has the same constitution as the plasma-based ion implantation, although the applied voltage is much lower. The crystallization on a low temperature substrate is assumed to arise from the simultaneous irradiation of ions extracted from plasma. In this report very low temperature crystallization of titanium nickel on polyimide substrate at 80°C (353K) was achieved by reducing the substrate heating due to the ion irradiation. The shape memory effect of the sheet was confirmed.