Pulsed-laser deposition of NiMnSb thin films at moderate temperatures

Thin films of the half-Heusler alloy NiMnSb, which is predicted by band-structure calculations to be a half-metallic ferromagnet, were grown on various substrates (Si and InAs) using pulsed-laser deposition. The growth process occurred at moderate substrate temperatures (190–210 °C), the lowest ever reported for producing crystalline films, which are necessary for making devices. We have identified a set of experimental conditions that allow the growth of highly crystalline thin films with nanoscale smooth surfaces. The morphology of the films was examined by atomic force microscopy and scanning electron microscopy. The structural, magnetic and electrical properties of the films are consistent with those of the polycrystalline pellet of NiMnSb used as target.