Sapphire electrical resistivity

The electrical resistivity is as high as 1016 Q cm [17]. This is good for electrical isolation as it has been used for SOS (silicon on sapphire), but inhibits vertical current flow through sapphire. 

The fabrication process of vanadium oxide (VO2) has also been studied using RBS/C. Since optical and electrical properties of VO2 are dramatically changed at 68°C due to phase transition, VO2 is regarded as one of the candidates for thermally activated electronic or optical switching devices for optical libers or sensors. To obtain the desired properties, the development of the fabrication process for very thin films, without crystalline defects on various substrates, is required. Single-crystalline VO2 thin films on (0001) plane of a sapphire substrate have been synthesized by a laser ablation method. The quality of VO2 was examined by X-ray diffraction and RBS/C method. The electrical resistance and the optical transmittance of the VO2 film were measured under increasing and decreasing temperatures. At a temperature of 68 °C, an abrupt transition of resistance from metal to... 

Experiments on N ion implantation in ZrN thin films were performed in order to investigate the process of N atom incorporation in this material and its influence on the structure, electrical resistivity, and superconductivity. Polycrystalline stoichiometric thin films of ZrN with thicknesses of about 250 nm deposited on single-crystal sapphire substrates by RF sputtering using Ar and Nj gas were used for the implantation samples. The partial pressure was 2 X 10 torr for Ar gas and in the range 1.7 to 8 X 10" torr for Nj gas, and the substrate temperature was maintained at 1000°C during the deposition. Samples had a well-developed polycrystalline structure and had values of the lattice parameter (Co) around 4.572 A, around 9.5 K, and residual resistivity (at UK) around 30 pQ cm. 

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