Comment on "Optical properties of CdTe1-xSx (0 <= x <= 1): Experiment and modeling" [J. Appl. Phys. 85, 7418 (1999)]

Wei [J. Appl. Phys. 85, 7418 (1999)] performed the room temperature spectro scopic ellipsometry to determine the dielectric function of CdTe1-xSx films . They have fit the obtained dielectric function using the Holden's model d ielectric function [Phys. Rev. B 56, 4037 (1997)], and derived conclusions about the line shape at the band gap E-0. However, their description of the fitting procedure is ambiguous, and some model parameters in Table I [J. A ppl. Phys. 85, 7418 (1999)] are missing which makes it impossible to reprod uce their calculations. Furthermore, the results of Wei [J. Appl. Phys. 85, 7418 (1999)] do not represent conclusive proof of the advantages of their approach over other models available in the literature. (C) 2000 American I nstitute of Physics. [S0021-8979(00)00116-X].