Open AccessDepth-dependent anti-reflection and enhancement of luminescence from Si quantum dots-based multilayer on nano-patterned Si substrates
Author(s) -
Yu Liu,
Jun Xu,
Hongcheng Sun,
Shantong Sun,
Wei Xu,
Ling Xu,
Kunji Chen
Publication year - 2011
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.19.003347
Subject(s) - materials science , luminescence , quantum dot , optoelectronics , reflection (computer programming) , nano , substrate (aquarium) , optics , etching (microfabrication) , absorption (acoustics) , total internal reflection , attenuation coefficient , silicon , nanotechnology , layer (electronics) , oceanography , physics , computer science , composite material , programming language , geology
Nano-sphere lithography technique was used to fabricate nano-patterned Si substrates with various depths by controlling the etching time. The depth-dependent broadband anti-reflection was observed and the reflectivity could be reduced to 5%. By depositing Si quantum dots/SiO2 multilayer on nano-patterned substrate, the reflection was further suppressed and luminescence intensity was significantly enhanced. The luminescence enhancement is dependent of the etching depth and the luminescence can be one order of magnitude stronger than that on flat substrate due to both the improved absorption of excitation light and the increase of light extraction ratio by nano-patterned structures.