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arXiv · 1507.05494

Large, light-induced capacitance enhancement in semiconductor junctions simulated by capacitor-resistor nets

B. Vainas
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Abstract

The equivalent circuit simulation of random resistors-capacitors (R-C) net, modified to include large capacitors interfacing between the random R-C bulk and the electrode surface, shows an enhancement of 3 orders of magnitude of the apparent real dielectric constant at low frequencies upon an introduction of resistors percolating paths in the bulk. The appearance of the bulk R-percolating paths can represent the photo-generated high conductivity state of semiconductors bulk, an effect supported by the experimental observation that, in parallel with the photo-enhancement of the real dielectric constant, its imaginary part is strongly enhanced as well. The addition of the photo-generated charge carriers strongly enhances bulks electrical conductivity, effectively confining the space charge region to the interface between bulks edge and the electrode. That could be a simple phenomenological explanation for the apparent dielectric constant enhancement upon illumination in photocells, not involving elaborate physical models.

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B. Vainas. 2015-07-20. Large, light-induced capacitance enhancement in semiconductor junctions simulated by capacitor-resistor nets. https://arxiv.org/abs/1507.05494

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