In this work, we report an extensive experimental and theoretical investigation of the voltage and temperature dependence of dielectric breakdown for both high-κ/SiO2 dual-layer and SiO2 single-layer dielectrics. Based on a two-step formulation of the breakdown process, a quantitative physics-based hydrogen release-reaction model is proposed. The model is successfully compared to the experimental data over a wide range of voltage, temperature, and thickness and considering both stress polarities. The model resolves three outstanding experimental observations: (1) the decrease of voltage acceleration exponents with increasing temperature, (2) the non-Arrhenius temperature dependence at low voltages, and (3) the large activation energy of ∼1.0 eV observed at high temperatures. © 2013 AIP Publishing LLC.