Reduction of optical reflection from InP semiconductor wafers after high-temperature annealing

TL;DR

This study demonstrates that high-temperature annealing significantly reduces optical reflection from InP wafers across a broad wavelength range, with the effect tunable by adjusting annealing conditions, due to oxide layer formation.

Contribution

It provides a detailed analysis of how high-temperature annealing induces oxide layers that decrease reflection, offering a method to control optical properties of InP wafers.

Findings

Reflection decreases significantly after annealing.

Reflection minimum can be tuned across 0.5 to 6 eV.

Oxide layer formation explains the reflection reduction.

Abstract

We observed and studied strong reduction of optical reflection from the surface of InP wafers after high-temperature annealing. The effect is observed over a wide range of the incident wavelengths, and in the transparency band of the material it is accompanied by increasing transmission. The spectral position of a minimum (almost zero) of the reflection coefficient can be tuned, by varying the temperature and the time of annealing, in the spectral range between 0.5 and 6 eV. The effect is explained by the formation of a uniform oxide layer, whose parameters (thicknesses and average index) are estimated by detailed modeling.