The high-thermal-stability amorphous (FfO(2))(1-x)(Al2O3)(x) thin films have been fabricated on p-type Si (100) using novel dual-beam pulse laser ablation technique. The microstructure, thermal stability and electrical properties of films have been studied by combinational characterization techniques. Silicides formed at the interface due to the Hf atom diffusion into Si substrate. The slight structure transition occurs at 1000 degrees C after 10 s rapid thermal annealing in N-2, which suggests that the (HfO2)(1-x)(Al2O3)(x) film has high thermal stability. High-frequency capacitance-voltage properties of capacitors show low equivalent oxide thickness at 1.7 nm for 10.0 nm films with high k value (similar to 22.5). The results indicate that the pseudo-binary (HfO2)(1-x)(Al2O3)(x) film is a promising candidate, which can withstand the high-temperature process for silicon-based industry. (c) 2005 Elsevier B.V. All rights reserved.