Conduction Studies in Silicon Nitride: Dark Currents and Photocurrents

Dark conduction and photoconduction phenomena in amorphous, stoichiometric Si
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films incorporated into metal-silicon nitride-silicon (MNS) structures are studied in detail. Results demonstrating the importance of hole conduction in Si
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thin films are presented. The importance of trapped space charge injected from the contacts is shown in an analysis of the effects of Si
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thickness and the choice of gate metal on conduction. Contact effects that are apparent in the current characteristics of thin Si
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layers become dominated by bulk conduction mechanisms as the silicon nitride film increases in thickness. Optical interference effects in photoconduction are used to determine the origin of photocarriers.