We report on the growth mechanisms of germanium nitride nanowires on the surface of crystalline Ge annealed in hydrazine vapor at different temperatures. In spite of the presence of water (and hence oxygen precursors) in hydrazine, the pure germanium nitride single crystal nanowires were produced in the temperature range of 480– C. At temperatures below C, the clusters were formed first at the Ge surface, followed by the nucleation and growth of nanowires through the Vapor-Liquid-Solid mechanism. The Vapor-Solid growth mechanism was observed at temperatures exceeding C, and Ge3N4 nanobelts were produced instead of nanowires with circular cross-sections. All nanostructures have the alpha germanium nitride structure; however, at the nucleation stage, the presence of beta Ge3N4 phase was also observed in the roots of nanowires. 1. Introduction Nanowire-based devices are considered nowadays as one of the most promising alternatives to conventional microelectronic facilities, which can promote further shrinking of device sizes and increase their functionality. The unique properties of one-dimensional (1D) nanowires arise due to their low dimensionality and hence by quantum-mechanical properties and surface dominated features. From the technological point of view, they have one more advantage. Due to high aspect ratios, the length of nanowires laies in the micrometer range reaching even millimeter sizes. Such “large” elements can be easily handled and manipulated when building different nanodevices and circuits. Germanium nitride has attracted much attention in recent years due to its unique properties and potential applications in different devices [1–3]. It can be used as a thin film material for the passivation of different semiconductors in metal-insulator-semiconductor devices [2, 4–8], as a buffer layer to grow the crystalline GaN film on Ge [9], material for plasmonic devices [1], effective nonoxide photocatalyst for overall water splitting [10], and stable negative electrode material for Li-ion batteries [11]. A new cubic spinel-structured phase of Ge3N4 (γ-phase) is harder than sapphire and can be used as a hard material [12]. As for the growth of one-dimensional germanium nitride nanostructures, there are only two papers dealing with Ge3N4 nanobelts and nanowires (NWs) [13, 14] produced at C. Earlier, we presented the preliminary results on the growth of nanostructured germanium nitride at significantly lower temperatures [15]. The purpose of this work is to investigate the initial stages of formation, growth mechanisms, structure, and morphology of
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