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arXiv · 1001.4264

Impact ionization fronts in Si diodes: Numerical evidence of superfast propagation due to nonlocalized preionization

Pavel Rodin·Andrey Minarsky·Igor Grekhov
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Abstract

We present numerical evidence of a novel propagation mode for superfast impact ionization fronts in high-voltage Si $p^+$-$n$-$n^+$ structures. In nonlinear dynamics terms, this mode corresponds to a pulled front propagating into an unstable state in the regime of nonlocalized initial conditions. Before the front starts to travel, field-ehanced emission of electrons from deep-level impurities preionizes initially depleted $n$ base creating spatially nonuniform free carriers profile. Impact ionization takes place in the whole high-field region. We find two ionizing fronts that propagate in opposite directions with velocities up to 10 times higher than the saturated drift velocity.

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Pavel Rodin, Andrey Minarsky, Igor Grekhov. 2010-01-24. Impact ionization fronts in Si diodes: Numerical evidence of superfast propagation due to nonlocalized preionization. https://doi.org/10.1063/1.3465302

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