화학공학소재연구정보센터
Current Applied Physics, Vol.16, No.3, 294-299, 2016
Electrical properties of the HfO2-Al2O3 nanolaminates with homogeneous and graded compositions on InP
For possible application to a gate dielectric in high-performance III-V transistors, nanolaminated HfO2-Al2O3 films with artificial compositional profiles were deposited on n-type InP substrates using atomic layer deposition. The films were vertically graded (HfO2 and Al2O3 at the surface and interface regions, respectively) and had a homogeneous composition. To compare their electrical properties, a similar physical thickness and capacitance-equivalent thickness (CET) were maintained, and the graded structure showed an increase in the Al2O3 content near the high-k and InP interface region without an increase in CET, which suppresses the In incorporation at the near-interface region and reduces the density of the interface trap. However, doing so results in a degradation of the leakage current characteristics under voltage stressing when compared to homogeneously-nanolaminated films. (C) 2015 Elsevier B.V. All rights reserved.