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arXiv · 2411.16892

A Versatile System for Photoconductance Decay Measurement Across a Wide Range of Semiconductor Materials

A. Bojtor·D. Krisztian·G. Parada·F. Korsos·S. Kollarics·G. Csosz·B. G. Markus·L. Forro·F. Simon
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Abstract

Time-resolved photoconductivity is widely used to characterize non-equilibrium charge-carrier lifetime, impurity content, and solar cell efficiency in a broad range of semiconductors. Most measurements are limited to the detection of reflection of electromagnetic radiation at a single frequency and a single photoexciting light wavelength. We present a time-resolved photoconductivity instrument that enables broadband frequency detection (essentially from DC to 100 GHz), temperature-dependent measurements, and multiple excitation photon energy. The measurement is realized with the help of a coplanar waveguide, which acts as an efficient antenna and whose performance was tested over 10 MHz-10 GHz. The instrument enables the study of surface and bulk charge-recombination specific processes.

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A. Bojtor, D. Krisztian, G. Parada, F. Korsos, S. Kollarics, G. Csosz, B. G. Markus, L. Forro, F. Simon. 2024-11-25. A Versatile System for Photoconductance Decay Measurement Across a Wide Range of Semiconductor Materials. https://doi.org/10.1103/pdrr-tpcm

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