Ordered arrays of high-quality single-crystalline alpha-Si3N4 nanowires (NWs) have been synthesized via thermal evaporation and detailed characteristics of the NWs have been analyzed by employing scanning electron microscope (SEM) along with energy dispersive spectroscopy (EDS), high-resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), X-ray photospectroscopy (XPS), infrared (IR), photoluminescence (PL) and in situ I-V measurements by STM/TEM holder. The microscopic results revealed that the NWs having diameter in the range of similar to 30-100 nm and length in microns. Furthermore, the NWs are found to be single crystalline grown along [0 0 1] direction. The elemental composition and valence states of elements are analyzed by EDS and XPS. The room temperature PL spectra exhibit a broad range visible emission band. The electron transport property of a single NW illustrates the symmetric I-V curve of a semiconductor. The possible growth mechanism is also briefly discussed. (C) 2009 Elsevier B.V. All rights reserved.