Optical properties of In1−xGaxP1−yAsy, InP, GaAs, and GaP determined by ellipsometry

Abstract

Refractive indices and absorption coefficients of In1−x Gax P1−yAsy for y = 0 to 1 lattice matched to InP and of GaAs and GaP have been measured by ellipsometry in the wavelength range between 365 and 1100 nm. The high-purity layers (7×1014<n<2×1016 cm−3) used here were grown by liquid phase epitaxy. The quaternary refractive indices were also calculated from the measured indices of the constituent binary compounds by averaging the quantity (ε−1)/(ε+2). The ε values were all taken at the same energy separation from the respective band gaps. The results of this new averaging procedure are compared with the measured indices and with the refractive index steps to InP deduced from lasers. In addition, the absorption coefficient of InP near the band gap was measured as a function of the doping level. Finally, the temporal growth of the natural oxide layer thickness dox on various InP and GaAs samples was determined by ellipsometry. For InP, the increase of dox is 0.39 nm per decade of time.

Optical constants of In0.53Ga0.47As/InP: Experiment and modeling

“…[6][7][8] Figures 1͑a͒ and 1͑b͒ correspond closely to the relevant data of Refs. 6, 7, and 8 in the ranges of 0.65 to 4.96, 1.13 to 3.4, and 1.5 to 5.1 eV, respectively.…”

“…Some authors have performed measurements of the In 0.53 Ga 0.47 As dielectric function, but have not modeled the experimental results. [6][7][8] Kelso et al 8 fit the numerical third derivative of the dielectric function, from which the authors were able to obtain the energies of features related to the E 1 , E 1 ϩ⌬ 1 critical points ͑CPs͒ ͑transitions along the equivalent ͗111͘ directions of the Brillouin zone͒. Nee and co-workers 9 modeled the optical constants including the discrete and continuum exciton contributions at E 0 but not at E 1 .…”

Wet Oxidation in a Square Sandwich Composite of GaAs/AlAs/GaAs

“…The reported values of refraction indices are 1.7884, 4.102, and 3.838 at wavelength 390 nm, and 1.7609, 3.666, and 3.013 at wavelength 780 nm for Al 2 O 3 , GaAs, and AlAs, respectively. [15][16][17][18] …”

Photonic crystal thin films of GaAs prepared by atomic layer deposition

“…However, the shift from the simple 2 relationship predicted by the Bragg equation can only be partially explained by the significant variation in refractive index and extinction coefficient of GaAs with wavelength, varying from n = 4.4 to 3.5 and k = 2.0 to 0.0 across the region studied ͑400-950 nm͒. 18,19 Furthermore, when infiltration calculations between the first and proposed second order features are compared ͑Table I͒ there is considerable disparity, with the second order features consistently overestimating the infill. This leads to the conclusion that the features are not purely due to a second order process but the convolution of 3.…”