We present direct imaging measurements of charge transport across a 1 cm x 1 cm x 4 mm-thick crystal of high purity silicon (∼15 kΩ-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.
@article{arxiv.1910.02169,
title = {High-field Spatial Imaging of Charge Transport in Silicon at Low Temperature},
author = {C. Stanford and R. A. Moffatt and N. A. Kurinsky and P. L. Brink and B. Cabrera and M. Cherry and F. Insulla and M. Kelsey and F. Ponce and K. Sundqvist and S. Yellin and B. A. Young},
journal= {arXiv preprint arXiv:1910.02169},
year = {2020}
}