Accurate I–V characterization of MOS/MS devices via Ocaya–Yakuphanoglu method

Abstract

A recent article [R. O. Ocaya and F. Yakuphanoğlu, Measurement 186, 110105 (2021)] presented the Ocaya–Yakuphanoglu (OY) method of device parameter extraction, wherein the current–voltage (I–V) equation of metal–oxide–semiconductor and metal–semiconductor devices in the thermionic emission (TE) model was reformulated as a differential equation. The solution revealed a fundamental but previously hidden symmetry in the device characteristics and rigorously proved that series resistance, Rs, is not constant but rather the instantaneous slope (dV/dI) of the I–V curve. The application of Rs reduced the TE equation and restored the true junction voltage, effectively removing bias-induced distortions in the extracted parameters. Consequently, the calculated barrier height, ΦB, is effectively invariant across bias, consistent with its intrinsic physical origin. Here, we extend the OY method by revealing a previously unrecognized relationship between Rs, ΦB, and applied bias, showing that it is intrinsic to Schottky transport and naturally explains the exponential decay with bias frequently observed in empirical studies; this enables reliable extraction of the diode parameters at their intrinsic limits, free from field induced distortions. Measurements on an Al/p-Si/2OD-TIFDKT/Al Schottky diode under 100 mW/cm2 illumination demonstrate that the OY method reproduces the expected trends in Rs and outperforms the Cheung and Norde methods.