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arXiv · 1910.02169

High-field Spatial Imaging of Charge Transport in Silicon at Low Temperature

C. Stanford·R. A. Moffatt·N. A. Kurinsky·P. L. Brink·B. Cabrera·M. Cherry·F. Insulla·M. Kelsey·F. Ponce·K. Sundqvist·S. Yellin·B. A. Young
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Abstract

We present direct imaging measurements of charge transport across a 1 cm x 1 cm x 4 mm-thick crystal of high purity silicon ($\sim$15 k$Ω$-cm) at temperatures of 5 K and 500 mK. We use these data to measure the lateral diffusion of electrons and holes as a function of the electric field applied along the [111] crystal axis, and to verify our low-temperature Monte Carlo software. The range of field strengths in this paper exceed those used in the previous study (DOI: 10.1063/1.5049691) by a factor of 10, and now encompasses the region in which some recent silicon dark matter detectors operate (DOI: 10.1103/PhysRevLett.121.051301). We also report on a phenomenon of surface charge trapping which can reduce expected charge collection.

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C. Stanford, R. A. Moffatt, N. A. Kurinsky, P. L. Brink, B. Cabrera, M. Cherry, F. Insulla, M. Kelsey, F. Ponce, K. Sundqvist, S. Yellin, B. A. Young. 2019-10-04. High-field Spatial Imaging of Charge Transport in Silicon at Low Temperature. https://doi.org/10.1063/1.5131171

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