Probe-device detecting single carriers: A new method for deep level characterization with nanosecond resolution

Single carriers emitted by deep levels can be detected with high time resolution in a probe device. The probe is a suitable junction structure, in which a carrier can trigger a macroscopic avalanche current pulse. A new method, conceptually similar to those employed for fluorescent and nuclear decays, can thus be used for studying deep levels: time-correlated carrier counting TCC. The method is here introduced and results of experimental feasibility tests are reported. The features of TCC are discussed, showing that its sensitivity, resolution and dynamic range make possible to extend investigations to levels so far not measured; for instance, relatively shallow levels with nanosecond lifetimes.