High-Performance Flexible Ultraviolet (UV) Phototransistor Using Hybrid Channel of Vertical ZnO Nanorods and Graphene

作者：Vinh Quang Dang; Tran Quang Trung; Le Thai Duy; Kim Bo Yeong; Siddiqui Saqib; Lee Wonil; Lee Nae Eung^*

来源：ACS Applied Materials & Interfaces, 2015, 7(20): 11032-11040.

DOI：10.1021/acsami.5b02834

• ZnO nanorods
• graphene
• field-effect transistor
• ultraviolet photodetector
• flexible

A flexible ultraviolet (UV) photodetector based on ZnO nanorods (NRs) as nanostructure sensing materials integrated into a graphene (Gr) field-effect transistor (FET) platform is investigated with high performance. Based on the negative shift of the Dirac point (V-Dirac) in the transfer characteristics of a phototransistor, high-photovoltage responsivity (R-V) is calculated with a maximum value of 3 x 10(8) V W-1. The peak response at a wavelength of similar to 365 nm indicated excellent selectivity to UV light. The phototransistor also allowed investigation of the photocurrent responsivity (R-I) and photoconductive gain (G) at various gate voltages, with maximum values of 2.5 X 10(6) A W-1 and 8.3 x 10(6), respectively, at a gate bias of 5 V. The UV response under bending conditions was virtually unaffected and was unchanged after 10 000 bending cycles at a bending radius of 12 mm, subject to a strain of 0.5%. The attributes of high stability, selectivity, and sensitivity of this flexible UV photodetector based on a ZnO NRs/Gr hybrid FET indicate promising potential for future flexible optoelectronic devices.

• 出版日期2015-5-27