Characterization of unannealed and annealed LTG:GaAs grown on SI-GaAs substrate for THz applications

Authors

Elizabeth Ann Prieto ⋅ PH National Institute of Physics, University of the Philippines Diliman
Aleena Maria Laganapan ⋅ PH National Institute of Physics, University of the Philippines Diliman
Ma. Herminia Balgos ⋅ PH National Institute of Physics, University of the Philippines Diliman
Christopher Que ⋅ PH Research Center for Development of Far-Infrared Region, University of Fukui
Elmer Estacio ⋅ PH National Institute of Physics, University of the Philippines Diliman
Kohji Yamamoto ⋅ JP Research Center for Development of Far-Infrared Region, University of Fukui
Masahiko Tani ⋅ JP Research Center for Development of Far-Infrared Region, University of Fukui
Armando Somintac ⋅ PH National Institute of Physics, University of the Philippines Diliman
Arnel Salvador ⋅ PH National Institute of Physics, University of the Philippines Diliman

Abstract

Characterization of low-temperature-grown Gallium Arsenide (LTG:GaAs) grown on semi-insulating (SI) GaAs substrate via molecular beam epitaxy (MBE) was presented. The substrate temperatures (Ts) considered were 220°C, 270°C and 310°C. High resolution x-ray diffraction showed that the LTG:GaAs was compressively strained with the SI-GaAs substrate. Raman spectroscopy confirmed the difference in the lattice constant of the LTG:GaAs epilayer and the SI-GaAs substrate. Upon in-situ annealing at temperature of 550°C for 5 minutes, the lattice parameter of the LTG:GaAs approached the conventional GaAs value. Terahertz (THz)-time domain spectroscopy revealed that annealed LTG:GaAs emits higher THz signal than unannealed LTG:GaAs. The increase in the THz amplitude was attributed to the increase in the surface depletion field of annealed LTG:GaAs caused by Fermi level pinning. Annealed LTG:GaAs grown at Ts=310°C emitted the highest THz radiation.

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Issue

2011: Proceedings of the 29th Samahang Pisika ng Pilipinas National Physics Congress

Article ID

SPP2011-2C-2

Section

Condensed Matter and Materials Physics

Published

2011-10-24

How to Cite

[1]

EA Prieto, AM Laganapan, MH Balgos, C Que, E Estacio, K Yamamoto, M Tani, A Somintac, and A Salvador, Characterization of unannealed and annealed LTG:GaAs grown on SI-GaAs substrate for THz applications, Proceedings of the Samahang Pisika ng Pilipinas 29, SPP2011-2C-2 (2011). URL: https://proceedings.spp-online.org/article/view/SPP2011-2C-2.