Physical and electrical characteristics of hafnium oxide (HfO(2)) films grown by pulsed laser deposition (PLD) technique and their application in AlGaN/GaN metal-insulator-semiconductor heterostructure field effect transistors (MIS-HFETs) have been investigated. The PLD-grown amorphous HfO(2) films exhibit good constituent uniformity and stoichiometry. The conduction band offset for HfO(2)/GaN heterostructure is evaluated to be 1.7 eV. The dielectric constant of HfO(2) is estimated as similar to 20 and the effective oxide charge density is similar to 8.9 x 10(11) cm(-2). The fabricated PLD-grown HfO(2) MIS-HFETs show a much better electrical performance than the conventional Schottky gate-HFETs, including a larger maximum drain current (31.5%), larger gate voltage swing (8.5%), smaller gate leakage current (two orders of magnitude), and smaller degradation rate at an elevated temperature operation. (C) 2010 Elsevier B.V. All rights reserved.