Characterization and numerical analysis of breakdown in thick amorphous SiO2 capacitors

•Investigation of thick amorphous silicon dioxide capacitors for integrated galvanic insulators.•TCAD simulations of charge transport in TEOS capacitors at high electric fields.•Time-dependent dielectric breakdown measurements at constant current and voltage-ramp stresses up to breakdown have been performed.•Charge injection at contacts, charge build-up due to intrinsic defectivity and impact-ionization have been intensively investigated.