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

This brief presents the effect of atomic layer deposition (ALD)-fabricated HfAlO<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">_x</i> gate-stacks on the interfacial chemistry and electrical properties of sputtered ErSmO/InP metal-oxide–semiconductor (MOS) capacitors. The ErSmO/HfAlO<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">_x</i> (1:2)/InP gate-stack displays the best electrical performance with a dielectric constant of 14.66, an interface state density (<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${D} _{\textit {it}}$ </tex-math></inline-formula>) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$5.48\times 10^{{11}}$ </tex-math></inline-formula> eV<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-}1 $ </tex-math></inline-formula>cm<inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$^{-}2 $ </tex-math></inline-formula>, a reduction in the electron effective mass of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.03~{m} _{{0}}$ </tex-math></inline-formula>, 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).