The paper reports on non-isothermal kinetics of transformation processes in magnetron sputtered alumina thin films with an amorphous and gamma-phase structure leading ultimately to the formation of the thermodynamically stable alpha-Al2O3 phase. Phase transformation sequences in the alumina films were investigated using differential scanning calorimetry (DSC) at four different heating rates (10, 20, 30, 40 degrees C/min). Three isoconversional methods (Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO) and Friedman (FR) method) as well as the invariant kinetic parameters (IKP) method were used to determine the activation energies for transformation processes. Moreover, the pre-exponential factors were determined using the IKP method. The kinetic models of the transformation processes were determined using the Malek method. It was found that the as-deposited structure of alumina films affects kinetics of the transformation processes. The film with the amorphous as-deposited structure heated at 40 degrees C/min transforms to the crystalline gamma phase at a temperature of similar to 930 degrees C (E-a,E-IKP =463 +/- 10 kJ/mol) and subsequently to the crystalline a phase at a temperature of similar to 1200 degrees C (E-a,E-IKP = 589 +/- 10 kJ/mol). The film with the crystalline gamma-phase structure heated at 40 degrees C/min is thermally stable up to similar to 1100 degrees C and transforms to the crystalline alpha phase (E-a,E-IKP = 511 +/- 16 kJ/mol) at a temperature of similar to 1195 degrees C. The empirical two-parameter Sestak-Berggren kinetic model was found to be the most adequate one to describe all transformation processes in magnetron sputtered alumina films. (C) 2013 Elsevier B.V. All rights reserved.