Visible-blind photodetector based on p-i-n junction GaN nanowire ensembles.

Institut d'Electronique Fondamentale, UMR 8622 CNRS, University Paris Sud XI, Orsay, France.
Nanotechnology (Impact Factor: 3.67). 08/2010; 21(31):315201. DOI: 10.1088/0957-4484/21/31/315201
Source: PubMed

ABSTRACT We report the synthesis, fabrication and extensive characterization of a visible-blind photodetector based on p-i-n junction GaN nanowire ensembles. The nanowires were grown by plasma-assisted molecular beam epitaxy on an n-doped Si(111) substrate, encapsulated into a spin-on-glass and processed using dry etching and metallization techniques. The detector presents a high peak responsivity of 0.47 A W(-1) at - 1 V. The spectral response of the detector is restricted to the UV range with a UV-to-visible rejection ratio of 2 x 10(2). The dependence on the incident power and the operation speed of the photodetector are discussed.

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