Kinetics and mechanism of atomic force microscope local oxidation on hydrogen-passiv ated silicon in inert organic solvents

Nanometer-scale FIO (field-induced oxidation) features were patterned on a hydrogen terminated silicon substrate using conductive atomic force microscopy (AFM) in an inert nonpolar organic liquid. An alternate logarithmetic model was proposed in which variations in the oxide growth rate were attributed to the transition of water at the AFM tip-sample junction from liquid water to vapor water. The oxide growth kinetics showed a reduction in the growth rate and a nonlinear dependence on voltage at long pulse times, as a function of applied bias and voltage pulse-time. It was observed that the oxide growth kinetics were consistent with a space-charge limited growth mechanism. The results suggested that in the presence of a water meniscus, the surrounding organic solvent may have little effect on the FIO process. It was concluded that FIO in hexadecane proceeds by a similar mechanism to FIO in the air.