Electrical detection of electron paramagnetic resonance: New possibilities for the study of point defects

Abstract

An investigation of the possibilities to measure electron paramagnetic resonance (EPR) with electrical detection (EDEPR) by measuring the microwave or radio frequency-induced change of the photoconductivity of various bulk Si samples containing shallow and deep level defects is presented. It was found that an electron-hole recombination mechanism via a donor (D0)-acceptor (A0) pair explains the observations and may be necessary if EDEPR is to be detected. A qualitative expression for the EDEPR signal intensity is presented. EDEPR offers sensitivity several orders of magnitude better than normal EPR. As few as 107 shallow P donors could be observed. In addition, EDEPR can be measured with spatial resolution allowing defect mapping.