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arXiv · 1601.05444

Probing surface recombination velocities in semiconductors using two-photon microscopy

Benoit Gaury·Paul Haney
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Abstract

The determination of minority-carrier lifetimes and surface recombination velocities is essential for the development of semiconductor technologies such as solar cells. The recent development of two-photon time-resolved microscopy allows for better measurements of bulk and subsurface interfaces properties. Here we analyze the diffusion problem related to this optical technique. Our three-dimensional treatment enables us to separate lifetime (recombination) from transport effects (diffusion) in the photoluminescence intensity. It also allows us to consider surface recombination occurring at a variety of geometries: a single plane (representing an isolated exposed or buried interface), two parallel planes (representing two inequivalent interfaces), and a spherical surface (representing the enclosing surface of a grain boundary). We provide fully analytical results and scalings directly amenable to data fitting, and apply those to experimental data collected on heteroepitaxial CdTe/ZnTe/Si.

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Benoit Gaury, Paul Haney. 2016-01-20. Probing surface recombination velocities in semiconductors using two-photon microscopy. https://doi.org/10.1063/1.4944597

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