IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Electronics Tuesday Sessions
       Session EL-TuP

Paper EL-TuP5
Optical Characterization of AgInGaS@sub 2@ Crystals for Nonlinear Optical Devices

Tuesday, October 30, 2001, 5:30 pm, Room 134/135

Session: Electronic Materials Poster Session
Presenter: K. Itani, Miyazaki University, Japan
Authors: K. Yoshino, Miyazaki University, Japan
K. Itani, Miyazaki University, Japan
H. Komaki, Miyazaki University, Japan
S. Chichibu, Tsukuba University, Japan
Y. Akaki, Miyazaki University, Japan
T. Ikari, Miyazaki University, Japan
Correspondent: Click to Email
I-III-VI@sub 2@ chalcopyrite semiconductors have made rapid progress for the solution of environmental and resources problems. CuInSe@sub 2@, especially, CuInGaSe@sub 2@, is expected as solar cell applications since it has large absorption coefficient of about 10@super 5@ cm@super Ð1@ at bandgap energy region. On the other hand, Ag-III-VI@sub 2@ chalcopyrite semiconductors, especially AgGaS@sub 2@, have been investigated as nonlinear optical materials. AgInGaS@sub 2@ is also much attracted as nonlinear optical materials for wide wavelength range.@footnote 1,2@ AgInGaS@sub 2@ has a bandgap energy from 1.9 to 2.7 eV. However, reports on the precise material characterizations of the AgInGaS@sub 2@ crystals are a few in comparison to other Ag based chalcopyrite semiconductors.The AgIn@sub X@Ga@sub 1-X@S@sub 2@ (X=0 ~ 1.0) crystals have been grown by the vertical gradient freezing (VGF) method. All samples indicate chalcopyrite structures, nearly stoichiometry and n-type by means of X-ray diffraction, electron probe microanalysis and thermoprobe analysis, respectively. Lattice constants of a and c axis are proportional with X values, indicating correspond to VegardÕs law. On the other hand, a free exciton (FE) emission band may be remarkably observed in the photoluminescence spectra at 77 K. This means that the samples are high purity. It is clear that the energy of the FE emission band shows a nonlinear dependence on the composition X values. Furthermore, the parameters of the refraction and permittivity also increase nonlinearly with increasing the composition X values. @FootnoteText@ @footnote 1@V. V. Badikov et al., J. Quantum Electron 10 (1980) 1302. @footnotre 2@O. G. Vlokh et al., Sov. Phys. Solid State 27 (1985) 787.