Silicon Nanowires-Based Schottky Diodes

Schottky Barrier Diodes are fabricated on both flat and silicon nanowires substrate. A simple and low-cost technique (Metal Assisted Chemical Etching) is used to obtain two distinct lengths (2.7 and 5.1 μm) for the silicon nanowires. Radio Frequency sputtering and electron beam evaporation techniques are used for metal deposition. A post-metallization annealing is performed, in forming gas atmosphere, for sintering the metallic contacts. Scanning electron microscopy images are used to examine both morphology and size of silicon nanowires. The superiority of deposition by sputtering is demonstrated, achieving a continuous film to cover the upper half of the silicon nanowires. Current-voltage measurements, in both forward and reverse bias, are used to describe the electrical properties of the fabricated samples. Better characteristics, equivalent to conventional Schottky diodes, are obtained when the silicon nanowires are more thoroughly coated. Best results are obtained for sputtered samples, whose silicon nanowires etching time is only 10 minutes.