Thermoelectric and micro-Raman measurements of carrier density and mobility in heavily Si-doped GaN wires

Combined thermoelectric-resistivity measurements and micro-Raman experiments have been performed on single heavily Si-doped GaN wires. In both approaches, similar carrier concentration and mobility were determined taking into account the non-parabolicity of the conduction band. The unique high conductivity of Si-doped GaN wires is explained by a mobility mu = 56 cm(2).V-1.s(-1) at a carrier concentration n = 2.6 x 10(20) cm(-3). This is attributed to a more efficient dopant incorporation in Si-doped GaN microwires as compared to Si-doped GaN planar layers. (C) 2013 AIP Publishing LLC.