Strong photo-response in a flip-chip nanowire p-Cu2O/n-ZnO junction

Physical and Materials Chemistry Division, National Chemical Laboratory, Dr Homi Bhabha Road, Pune, India.
Nanoscale (Impact Factor: 6.74). 11/2011; 3(11):4706-12. DOI: 10.1039/c1nr10665a
Source: PubMed

ABSTRACT Cu(2)O nanoneedles are synthesized on a copper substrate by a simple anodization and reducing ambient annealing protocol. ZnO nanorods are grown on ITO coated glass by a low temperature chemical route. The electronic and photo-response properties of the p-Cu(2)O/n-ZnO flip-chip heterojunction are then studied and analyzed. We show that the I-V characteristic is rectifying and the junction exhibits a good photoresponse (∼120% under 1 V reverse bias) under AM 1.5 (1 Sun) illumination. This nano-heterojunction photo-response is far stronger as compared to that of a pulsed laser deposited thin film p-Cu(2)O/n-ZnO heterojunction, which can be attributed to higher junction area in the former case.

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