Temperature dependence of ambipolar diffusion in silicon-on-insulator

Hui Zhao

doi:10.1063/1.2898711

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arXiv · 0806.3900

Temperature dependence of ambipolar diffusion in silicon-on-insulator

Hui Zhao

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Abstract

Spatiotemporal dynamics of electron-hole pairs locally excited in a silicon-on-insulator structure by indirect interband absorption are studied by measuring differential transmission caused by free-carrier absorption of a probe pulse tuned below the bandgap, with 200-fs temporal and 3-micrometer spatial resolution. From sample temperatures of 250 K to 400 K, the ambipolar diffusivity decreases, and is similar to reported values of bulk silicon. Cooling the sample from 250 K to 90 K, a decrease of ambipolar diffusivity is observed, indicating important influences of defects and residual stress on carrier diffusion. No detectable density dependence of ambipolar diffusivity is observed.

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Hui Zhao. 2008-06-24. Temperature dependence of ambipolar diffusion in silicon-on-insulator. https://doi.org/10.1063/1.2898711

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