Alkyl monolayer passivated metal-semiconductor diodes: 2: Comparison with native silicon oxide

To understand the electrical properties at passivated metal semi-conductor interfaces, two types of mercury - insulator - silicon (n-type) junctions, Hg\C10H21-Si and Hg\SiO2 - Si, were fabricared and their current - voltage and capacitance - voltage characteristics compared. Both of them exhibited near-ideal rectifying characteristics with an excellent saturation current at reverse bias, which is in contrast to the previously reported ohmic behavior of an unmodified mercury - silicon junction. The experimental results also indicated that the n-decyl monolayer passivated junction possesses a higher effective barrier height, a lower ideality factor (that is, closer to unity), and better reproducibility than that of native silicon oxide. In addition, the dopant density and build-in potential, extracted from capacitance - voltage measurements of these passivated mercury - silicon junctions, revealed that alkyl monolayer derivatization does not alter the intrinsic properties of the silicon substrate. The calculated surface state density at the alkyl monolayer \ silicon interface. The present study increases the possibility of using advanced organic materials as ultrathin insulator layers for miniaturized, silicon-based microelectronic devices.