Effect of high-pressure H(2)O treatment on elimination of interfacial GeO(X) layer between ZrO(2) and Ge stack

Abstract

This investigation demonstrates the effect of high-pressure H(2)O treatment on the elimination of the interfacial germanium suboxide (GeO(X)) layer between ZrO(2) and Ge. The formation of GeO(X) interlayer increases the gate-leakage current and worsen the controllability of the gate during deposition or thermal cycles. X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy reveal that high-pressure H(2)O treatment eliminates the interfacial GeO(X) layer. The physical mechanism involves the oxidation of non-oxidized Zr with H(2)O and the reduction of GeO(X) by H(2). Treatment with H(2)O reduces the gate-leakage current of a ZrO(2)/Ge capacitor by a factor of 1000. (C) 2011 American Institute of Physics. [doi:10.1063/1.3627187]