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In this paper, we present the preparation and characterization of Schottky barrier diodes based on silicon carbide with various Schottky metal layer thickness values. In this structure, molybdenum and aluminum were employed as the Schottky barrier metal and top electrode, respectively. Schottky metal layers were deposited with thicknesses ranging from 1000 to 3000 A, and top electrodes were deposited with thickness as much as 3000 A. The deposition of both metal layers was performed using the facing target sputtering (FTS) method, and the fabricated samples were annealed with the tubular furnace at 300 degrees C under argon ambient for 10 min. The Schottky barrier height, series resistance, and ideality factor was calculated from the forward I-V characteristic curve using the methods proposed by Cheung and Cheung, and by Norde. For as-deposited Schottky diodes, we observed an increase of the threshold voltage (V(T)) as the thickness of the Schottky metal layer increased. After the annealing, the Schottky barrier heights (SBHs) of the diodes, including Schottky metal layers of over 2000 A, increased. In the case of the Schottky metal layer deposited to 1000 A, the barrier heights decreased due to the annealing process. This may have been caused by the interfacial penetration phenomenon through the Schottky metal layer. For variations of V(T), the SBH changed with a similar tendency. The ideality factor and series resistance showed no significant changes before or after annealing. This indicates that this annealing condition is appropriate for Mo SiC structures. Our results confirm that it is possible to control V(T) by adjusting the thickness of the Schottky metal layer.

A facile method to facilitate epitaxial lateral overgrowth (ELO) of gallium nitride (GaN) was developed by using single-walled carbon nanotubes (SWCNTs). High-quality GaN was achieved on sapphire by simply coating the SWCNTs as an intermediate layer for stress and defect mitigation. SWCNTs maintained their integrity at high reaction temperature and led to suppression of edge dislocations and biaxial stress relaxation by up to 0.32 GPa in a GaN template layer. InGaN/GaN multi-quantum-well light-emitting diodes (LEDs) on this high-quality GaN template offered enhanced internal quantum efficiency and light output power with reduced efficiency droop. The method developed here has high potential to replace current ELO methods such as patterned sapphire substrates or buffer layers like SiO2 and SiNx.

In this study, Schottky barrier diodes based on silicon carbide with various levels of Schottky metal layer input power were prepared and characterized. In this structure, molybdenum and aluminum were employed as the Schottky metal and top electrode, respectively. Schottky metal layers were deposited with input power ranging from 30 to 210 W. Schottky metal layers and top electrodes were deposited with a thickness of 3000 Å. The Schottky barrier heights, series resistances, and ideality factor were calculated from current–voltage (I–V) curves obtained using the Cheung–Cheung and Norde methods. All deposition processes were conducted using a facing targets sputtering system. Turn on voltage was minimized when the input power was 90 W, at which point electrical characteristics were observed to have properties superior to those at other levels of input power.