SiO2hole traps with small cross section (&sgr;≤10−15cm2) in Al gated metal–oxide–silicon capacitors have been studied using vacuum ultraviolet hole injection in combination with capacitance voltage measurements. The data show that small &sgr; hole traps are related to H/hole pairs or protons trapped in the oxide. Since accumulated positive charge and H vanish simultaneously from the oxide in times of the order of 102s, it is proposed that they migrate together through the oxide as a proton. The small &sgr; hole traps are not associated with defects in the as‐grown oxide; they are generated by radiation induced release of atomic H. Their number is governed by the rates of release and of removal (dimerization) of atomic H. ©1995 American Institute of Physics.