TY  - JOUR
AU  - Bittkau, K.
AU  - Carius, R.
TI  - Near-field study of optical modes in randomly textured ZnO thin films
JO  - Superlattices and microstructures
VL  - 42
SN  - 0749-6036
CY  - Oxford [u.a.]
PB  - Elsevier Science, Academic Press
M1  - PreJuSER-61534
SP  - 47 - 51
PY  - 2007
N1  - Record converted from VDB: 12.11.2012
AB  - We report on near-field scanning optical microscopy measurements on randomly textured ZnO thin films. These films are commonly used as transparent conducting oxide in thin-film solar cells. Textured interfaces are used to increase the scattering of light, which leads to a better light trapping in the solar cell. Here, both the topography and the local transmission are measured with a tapered fiber tip with very high spatial resolution. By varying the distance of the tip and the wavelength of the incident light, the optical profile is visualized and reveals a strong confinement of light on a subwavelength scale which corresponds to ridges in the surface structure. The confinement of light results from guided optical modes in the ZnO which are accompanied by a modulated evanescent field in air. No corresponding structure to this modulation is found in the topography. These results give new insight for further improvement of light trapping in solar cells. (c) 2007 Elsevier Ltd. All rights reserved.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000250271200009
DO  - DOI:10.1016/j.spmi.2007.04.002
UR  - https://juser.fz-juelich.de/record/61534
ER  -