Highly selective spectral response with enhanced responsivity of n-ZnO/p-Si radial heterojunction nanowire photodiodes

作者：Um Han Don; Moiz Syed Abdul; Park Kwang Tae; Jung Jin Young; Jee Sang Won; Ahn Cheol Hyoun; Kim Dong Chan; Cho Hyung Koun; Kim Dong Wook^*; Lee Jung Ho

来源：Applied Physics Letters, 2011, 98(3): 033102.

DOI：10.1063/1.3543845

A radial heterojunction nanowire diode (RND) array consisting of a ZnO (shell)/Si (core) structure was fabricated using conformal coating of a n-type ZnO layer that surrounded a p-type Si nanowire. In both ultraviolet (UV) and visible ranges, the photoresponsivity of the RND was larger than that of a planar thin film diode (PD) owing to the efficient carrier collection with improved light absorption. Compared to a PD, in the forward bias, a 6 mu m long RND resulted in a similar to 2.7 times enhancement of the UV responsivity at lambda = 365 nm, which could be explained based on the oxygen-related hole-trap mechanism. Under a reverse bias, UV-blind visible detection was observed while the UV response was suppressed.

• 出版日期2011-1-17