Improving the photoluminescence properties of self-assembled InAs surface quantum dots by incorporation of antimony

• Published in: Applied surface science Vol. 257; no. 21; pp. 8784 - 8787
• Main Authors: Chiang, C.H., Wu, Y.H., Hsieh, M.C., Yang, C.H., Wang, J.F., Chen, Ross C.C., Chang, L., Chen, J.F.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.08.2011; Elsevier
• Subjects: Antimony; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Density; Exact sciences and technology; InAs; Indium arsenides; Photoluminescence; Physics; Quantum dots; Segregation; Segregations; Surface quantum dot; Surfactant; Surfactants; Surface quantum dot; Antimony; Surfactant; InAs; Segregation; Self-assembly; Inorganic compounds; Semiconductor materials; Quantum dots; Photoluminescence; Surfactants; Indium arsenides
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2011.04.006

► This study investigates the surfactant effect and segregation effect from InAs surface quantum dots (SQDs) by incorporating antimony (Sb) into the QD layers. ► The Sb surfactant effect can extend planar growth and suppress dot formation. ► Photoluminescence reveals an enhancement in the optical properties of InAs SQDs as the Sb BEPs increase. ► Transmission electron microscopy images demonstrate that Sb segregates close to the surface of the SQD. This study investigates the effects of surfactant and segregation from InAs surface quantum dots (SQDs) by incorporating antimony (Sb) into the QD layers. The Sb surfactant effect extends planar growth and suppresses dot formation. Incorporating Sb can reduce the density of SQDs by more than two orders of magnitude. Photoluminescence (PL) reveals enhancement in the optical properties of InAs SQDs as the Sb beam equivalent pressure (BEP) increases. This improvement is caused by the segregation of Sb on the surface of SQDs, which reduces non-radiative recombination and suppresses carrier loss. The dark line at the SQDs surface in the transmission electron microscopic image suggests that the incorporated Sb probably segregates close to the surface of the SQDs. These results indicate a marked Sb segregation effect that can be exploited to improve the surface-sensitive properties of SQDs for biological sensing.