Reflectivity spectroscopy of the effects of successive etching of AlAs/AlGaAs Distributed Bragg Reflectors

Authors

Jairrus Braga Publico ⋅ PH National Institute of Physics, University of the Philippines Diliman
Alexander E. De Los Reyes ⋅ PH National Institute of Physics, University of the Philippines Diliman
John Daniel E. Vasquez ⋅ PH National Institute of Physics, University of the Philippines Diliman
Karl Cedric V. Gonzales ⋅ PH National Institute of Physics, University of the Philippines Diliman
Gerald Angelo R. Catindig ⋅ PH National Institute of Physics, University of the Philippines Diliman
Elizabeth Ann P. Prieto ⋅ PH National Institute of Physics, University of the Philippines Diliman
Rommel Jagus ⋅ PH National Institute of Physics, University of the Philippines Diliman
Kerphy Liandro Patrocenio ⋅ PH National Institute of Physics, University of the Philippines Diliman
Elmer S. Estacio ⋅ PH National Institute of Physics, University of the Philippines Diliman
Arnel Salvador ⋅ PH National Institute of Physics, University of the Philippines Diliman
Armando Somintac ⋅ PH National Institute of Physics, University of the Philippines Diliman

Abstract

The effects on the reflectivity spectra of successive etching of an AlAs/AlGaAs Distributed Bragg Reflector are studied. Etching was done using base piranha solution (NH₄OH + H₂O₂ + H₂O) and characterization was done using a normal reflectivity set-up. The central reflectivity of the DBR was observed at 9100Å, with full-width at half maximum of 875Å. With the design wavelength of 8500Å, the disparity was attributed to the error in either layer thickness or molar composition of Al in Al_xGa_1-xAs. The error was found improbable for Al mole fraction alone. When error caused by layer thickness was investigated, it was found that the layer thickness for AlAs was 767Å with 8.3% error, and AlGaAs 676Å with 10.6% error. Each successive etching reduced the peak reflectance and increased the full-width at half maximum of the reflectance spectra. A big drop in reflectivity was also observed after the 6^th etching, and the peak reflectivity of the DBR were less than the expected values. These observations were attributed to the changes in the etchant and the surface morphology produced by etching.

Downloads

Issue

2018: Proceedings of the 36th Samahang Pisika ng Pilipinas Physics Conference

Article ID

SPP-2018-PC-49

Section

Poster Session C (Mathematical Physics, Optics, and Interdisciplinary Topics)

How to Cite

[1]

JB Publico, AE De Los Reyes, JDE Vasquez, KCV Gonzales, GAR Catindig, EAP Prieto, R Jagus, KL Patrocenio, ES Estacio, A Salvador, and A Somintac, Reflectivity spectroscopy of the effects of successive etching of AlAs/AlGaAs Distributed Bragg Reflectors, Proceedings of the Samahang Pisika ng Pilipinas 36, SPP-2018-PC-49 (2018). URL: https://proceedings.spp-online.org/article/view/SPP-2018-PC-49.