Separation of the surface and bulk recombination in silicon by means of transient photoluminescence

The bulk and surface recombination determine the electrical performance of many semiconductor devices. Yet, the experimental determination and separation of both surface and bulk recombination rate remains challenging. This paper presents the measurement and separation of the bulk and surface recombination in silicon by means of time resolved photoluminescence spectroscopy. The high temporal resolution of the applied time correlated single photon counting technique is exploited to access the photoluminescence response of a silicon sample upon pulsed excitation in the nanosecond to millisecond regime on a sub-cm2 area. A rigorous data fitting algorithm based on two dimensional numeric simulations of the induced charge carrier dynamics is applied to extract all information on bulk and surface recombination properties from the recorded photoluminescence transients. Using different samples with symmetric as well as asymmetric surface recombination properties, we demonstrate the capabilities of the proposed contactless and nondestructive technique, which may be applicable to silicon based mono- or multi-junction devices.