Effect of rapid thermal annealing on the optical properties of GaAsSb alloys

Xian Gao,Jinhua Li,Xueying Chu,Xiaohui Ma,Zhipeng Wei,Jilong Tang,Rui Chen,Xiaohua Wang,Dengkui Wang,Xuan Fang,Dan Fang

doi:10.1364/ome.7.001971

Abstract

GaAsSb ternary alloys are fundamental components of advanced electronic and optoelectronic devices in the future. The presence of localized states could greatly affect the optical properties in GaAsSb alloy, which depend on the fluctuation of alloy composition. In order to optimize the optical properties, GaAsSb alloys were treated by rapid thermal annealing (RTA) at different temperatures, and the optical behaviors of the annealed samples were investigated in detail. During RTA, a significant reduction of the localized states was observed by photoluminescence (PL) spectral analysis. Furthermore, the RTA process also altered the distribution of the components of the GaAsSb alloy, which caused a slight red-shift of the maximum PL peak at 150 K. The relationship between the localized states and the temperature of the RTA process was also investigated. The process involving the conversion of localized carriers to free carriers was proposed. Under the suitable RTA conditions, the Sb component was homogenized and the depth of carrier localization was decreased.

Highlights

Owing to their advantages in potential optoelectronic and electronic device applications [1,2,3,4,5], III-V semiconductors based on GaAs and GaSb materials have attracted great attention in recent years
The results showed that the suitable rapid thermal annealing (RTA) conditions promoted the homogeneous distribution of components and allowed manipulating the depth of localized states in GaAsSb alloys
GaAsSb alloys were grown on a GaAs substrate by molecular beam epitaxy (MBE), and were treated by RTA at various temperatures between 500 °C and 700 °C in this research

Summary

Introduction

Owing to their advantages in potential optoelectronic and electronic device applications [1,2,3,4,5], III-V semiconductors based on GaAs and GaSb materials have attracted great attention in recent years. Rapid thermal annealing (RTA), in which the material is heated to a high temperature for a period of seconds, is beneficial for the healing of certain types of structural defects, the relaxation of residual stress, the prevention of diffusion and the improvement of the alloy uniformity. With these advantages, the RTA process could be developed as an effective method to modulating the properties of localized states. The results showed that the suitable RTA conditions promoted the homogeneous distribution of components and allowed manipulating the depth of localized states in GaAsSb alloys

Experimental

Results and discussion

Conclusion