Parametric modeling of the dielectric functions of InAsxP1 − x alloy films on InP

• We report an analytic expression of the dielectric functions of InAsxP1 − x films.
• The dielectric function spectra are obtained by spectroscopic ellipsometry.
• To obtain analytic expressions for these data, we use the parametric model.
• Dielectric functions of arbitrary compositions can be calculated.

We report an analytic expression that accurately represents the dielectric functions ε = ε1 + iε2 from 1.5 to 6.0 eV of InAsxP1 − x alloy films over the entire composition range 0 ≤ x ≤ 1. We use the parametric model (PM), which describes the dielectric functions of semiconductor materials as a sum of Gaussian-broadened polynomials. The dielectric function spectra are those that we obtained previously by spectroscopic ellipsometry for the specific compositions x = 0.00, 0.13, 0.40, 0.60, 0.80, and 1.00. The PM reconstructions are in excellent agreement with the data. With the information provided here, dielectric functions of arbitrary compositions can be calculated.