Dependence of oxygen partial pressures on structural and electrical characteristics of HfAlO (Hf:Al=1:1) high-k gate dielectric ultra-thin films grown on the compressively strained Si83Ge17by pulsed-laser deposition were investigated. The microstructure and the interfacial structure of the HfAlO thin films grown under different oxygen partial pressures were studied by transmission electron microscopy, and the their electrical properties were characterized by capacitance-voltage (C-V) and conductance-voltage measurements. Dependence of interfacial layer thickness and C-V characteristics of the HfAlO films on the growth of oxygen pressure was revealed. With an optimized oxygen partial pressure, an HfAlO film with an effective dielectric constant of 16 and a low interface state density of ∼2.1×1010cm-2eV-1was obtained.
- High-k dielectric
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Electronic, Optical and Magnetic Materials