Photoconductivity in single AlN nanowires by subband gap excitation
Journal
Applied Physics Letters
Journal Volume
96
Journal Issue
6
Pages
062104-1 - 062104-3
Date Issued
2010
Author(s)
Huang, H.M.
Chen, R.S.
Chen, H.Y.
Liu, T.W.
Kuo, C.C.
Chen, C.P.
Hsu, H.C.
Chen, K.H.
Abstract
Photoconductivity of individual aluminum nitride (AlN) nanowires has been characterized using different subband gap excitation sources. It is interesting that both positive (under 1.53 and 2.33 eV excitations) and negative (under 3.06 and 3.81 eV excitations) photocurrent responses are observed from the wide band gap nitride nanowires. The negative photoconductivity, which is attributed to the presence of electron trap and recombination center in the bulk of AlN, is capable to be inversed by a strong positive photoconductive mechanism of surface while changes the ambience from the atmosphere to the vacuum. An oxygen molecular sensitization effect is proposed to be the reason resulting in the enhancement of positive photocurrent and the inversion of negative photoresponse in the vacuum. Understanding of the diverse photoconductivity and its molecular effect is of great importance in the development of energy-selective and highly sensitive nanowire photodetector of AlN in the visible and ultraviolet ranges. © 2010 American Institute of Physics.
SDGs
Other Subjects
AlN; AlN nanowire; Highly sensitive; Molecular effect; Photocurrent response; Photoresponses; Recombination centers; Subband-gap; Visible and ultraviolet; Wide band gap; Molecular oxygen; Nanowires; Nitrides; Optoelectronic devices; Photoconductivity; Vacuum; Aluminum nitride
Publisher
American Institute of Physics
Type
journal article