Microwave irradiation causes voltage fluctuations in solid state nanodevices. Such an effect is relevant in atomic electronics and nanostructures for quantum information processing, where charge or spin states are controlled by microwave fields and electrically detected. Here, the variation of the characteristic times of the capture and emission of a single electron by an interface defect in submicron metal oxide semiconductor field effect transistor is calculated and measured as a function of the microwave power. In the model, the frequency of the voltage modulation is assumed to be large if compared to the inverse of the characteristic times. The variation of the characteristic times under microwave irradiation is quantitatively predicted from the microwave frequency dependent stationary current generated by the voltage fluctuation itself. The expected values agree with the experimental measurements. The reported …