Modification of Interface Quality and Electrical Performance of ErSmO/InP Gate-Stacks by ALD-Driven HfAlOx Interlayers

Abstract

This brief presents the effect of atomic layer deposition (ALD)-fabricated HfAlO _x gate-stacks on the interfacial chemistry and electrical properties of sputtered ErSmO/InP metal-oxide–semiconductor (MOS) capacitors. The ErSmO/HfAlO _x (1:2)/InP gate-stack displays the best electrical performance with a dielectric constant of 14.66, an interface state density ( ${D} _{\textit {it}}$ ) of $5.48\times 10^{{11}}$ eV $^{-}1 $ cm $^{-}2 $ , a reduction in the electron effective mass of $0.03~{m} _{{0}}$ , and an increase in barrier height to 0.97 eV. InP-MOS capacitors were systematically analyzed under temperature-dependent conditions to ascertain the transition of conduction mechanisms. In particular, trap density level in InP-MOS capacitors has been investigated based on low-frequency noise (LFN) measurements. The development of gate-stacks indicates an avenue for next-generation MOS field-effect transistors (MOSFETs).