Open AccessEnhanced Electroluminescence From Si Quantum Dots-Based Light-Emitting Devices With Si Nanowire Structures and Hydrogen Passivation
Author(s) -
Y. Y. Zhai,
Y. Q. Cao,
Z. W. Lin,
M. Q. Qian,
J. Xu,
W. Li,
L. Xu,
K. J. Chen
Publication year - 2016
Publication title -
ieee photonics journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.725
H-Index - 73
eISSN - 1943-0655
pISSN - 1943-0647
DOI - 10.1109/jphot.2016.2600373
Subject(s) - engineered materials, dielectrics and plasmas , photonics and electrooptics
Enhanced electroluminescence (EL) has been achieved from the light-emitting devices containing Si quantum dots/SiO2 multilayers deposited on Si nanowire arrays because of the good antireflection characteristics of Si nanowire structures, which improves the light extraction efficiency. However, it is found that the EL is first enhanced with increasing the depth of the Si nanowires and then reduced to further increase the depth, though it exhibits the lowest reflectance (∼3%), which may be due to the increased surface defect states after long time etching, as revealed by electron spin resonance measurements. It is demonstrated that the posthydrogen plasma annealing treatments can passivate the surface defect states which, in turn, improve device performance. The best device shows the turn-on voltage as low as 3.5 V, and the EL intensity of devices on Si nanowire arrays is enhanced 16-fold, compared with that of flat one.