Investigation of carbon–silicon Schottky barrier diodes

摘要

The fabrication of high performance Schottky barrier diodes (SBDs) between silicon and two different types of conductive carbon films is reported. The diodes are fabricated by simply spin coating and annealing of photoresist films (PPF) or by the chemical vapour deposition of pyrolytic carbon (PyC) onto n-type silicon wafers. After patterning with a metal hardmask and structural transfer a defined diode interface has achieved. The current–voltage characteristics of the SBDs were recorded in ambient. Diode parameters including the ideality factor n, the barrier height wB and the series resistance RS were extracted using an extended thermionic emission theory and the Norde function. The ideality factors were n=1.25 for the PPF-Si diodes and n=1.45 for the PyC-Si diodes. The values are close to those of commercial products and therefore, these highly durable and easily fabricated diodes may prove to be commercially viable. Moreover, the diode characteristics can be used to evaluate the electrical properties of thin carbon films.