A 0.5-μm-thick polycrystalline silicon Schottky diode with rectification ratio of 10⁶

Polycrystalline Si films, 0.5-μm thick, were obtained as a result of metal-induced growth by sputtering from a Si target on 25 nm thick Ni prelayers at 525°C. Silicon grew heteroepitaxially on the NiSi₂ layer formed due to the reaction between the sputtered Si atoms and Ni. Schottky diodes were fabricated on the Si films by deposition of a Schottky metal on the front surface of the film while Ni disilicide provided an intimate ohmic contact at the back. A Pd/n-Si diode using an n-Si film annealed for 2 h at 700°C in forming gas demonstrated a rectification ratio of 10⁶, while an as-deposited p-Si film provided an Al/p-Si diode with rectification of five orders of magnitude. Schottky barrier properties are briefly discussed.