Characterisation of Cd1-xMgxSe solid solutions by spectroscopic ellipsometry
2001 (English)In: Vacuum, ISSN 0042-207X, Vol. 63, no 1-2, 233-239 p.Conference paper (Other academic)
Optical properties of bulk Cd1-xMgxSe mixed crystals, grown from a CdSe, Mg, and Se melt by the Bridgman method, are presented. The alloys have a wurtzite type structure in the investigated range of composition, i.e. for 0 = x = 0.4. Measurements of the complex pseudo-dielectric function, = + ie2(?)>, were performed at room temperature in the photon energy range of 1.25-4.5 eV, using a computer-controlled variable angle of incidence ellipsometer. The spectral dependence of the effective refractive index and the absorption coefficient were also derived. The structure observed in the dielectric functions, attributed to the interband transitions E0, E0 + ?0 and E1, have been analysed by fitting the and d2/d?2 spectra to the damped harmonic oscillator and critical-point line shapes, respectively. For all critical points, the energy increases with increasing Mg concentration. The ellipsometric results of a fundamental band-gap shift due to Mg content are compared with the rate of increase of the excitonic energy, derived from photoluminescence spectra. © 2001 Elsevier Science Ltd.
Place, publisher, year, edition, pages
2001. Vol. 63, no 1-2, 233-239 p.
Dielectric function, II-VI semiconductors, Photoluminescence, Spectroscopic ellipsometry
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-47323DOI: 10.1016/S0042-207X(01)00197-XOAI: oai:DiVA.org:liu-47323DiVA: diva2:268219