PREPARATION OF SN1-XPBXS THIN FILMS FOR OPTOELECTRONIC APPLICATION

Thin films and nanorods of Sn1–XPbXS with orthorhombic crystal structure and c-axis oriented perpendicular to the substrate surface were grown by hot wall vacuum deposition (HWVD) method. The nanorods grew via a selfconsuming vapor–liquid–solid (VLS) mechanism by means of Sn-droplets onto the surface of an underlying thin film. The former one consists of stacked blocks with their c-axis always parallel to the growth direction. However, each block is alternately rotated around the [001] against its underlying and following one. As revealed by composition analysis there is no composition gradient across or within the nanorods and the underlying film. The rods were about 510-7 m high, 310-7 m in diameter. The droplet at the top of rods consists of Sn with small trace of Pb and S. The density of rods arranged like a lawn depends on the metal ratio and substrate temperature. The as-grown Sn1-XPbXS samples showed p-type electrical conductivity. The increase of lead atoms concentration leads to decrease of Seebeck coefficient and decrease of conductivity.