Toward a systematic understanding of photodetectors based on individual metal oxide nanowires

JOURNAL OF PHYSICAL CHEMISTRY C 112:14639-14644. DOI: 10.1021/jp804614q

ABSTRACT We present a set of criteria to optimize photodetectors based on n-type metal oxide nanowires and a comparison methodology capable of overcoming the present lack of systematic studies dealing with such devices. The response of photoconductors is enhanced following different fabrication strategies, such as diminishing the distance between the electrical contacts, increasing the width of the photoactive area, or improving the electrical mobility of the nanomaterials. The validity of the theoretical background is verified by experimental results obtained with devices based on ZnO nanowires. The performances of our devices show that the normalized gain of single ZnO nanowire-based photodetectors exceeds those of thin films.

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May 28, 2014