Influence of as on the Morphologies and Optical Characteristics of GaSb/GaAs Quantum Dots

Author

Tseng, Chi-Che ; Mai, Shu-Cheng ; Lin, Wei-Hsun ; Wu, Shung-Yi ; Yu, Bang-Ying ; Chen, Shu-Han ; Lin, Shih-Yen ; Shyue, Jing-Jong ; Wu, Meng-Chyi

Author_Institution

Inst. of Electron. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan

Volume

47

Issue

3

fYear

2011

fDate

3/1/2011 12:00:00 AM

Firstpage

335

Lastpage

339

Abstract

The influence of As atoms on the morphologies of GaSb quantum dots (QDs) is investigated. Without any special treatment, GaSb quantum rings (QRs) are observed in the embedded GaSb layer even when the uncapped layer reveals QD like morphologies. With intentional As supply after the uncapped GaSb QD deposition, a QD to QR transition is observed. The phenomenon suggests that insufficient Sb atoms on the GaSb QDs would lead to the QD to QR transition as in the case of embedded GaSb layers. With extended Sb soaking time following GaSb deposition, QD structures could be well maintained for the embedded GaSb layers. A light-emitting diode operated at room temperature is fabricated based on the GaSb/GaAs QD structure. Identical peak positions in photoluminescence and electroluminescence (EL) spectra of the device show that type-II GaSb QDs are responsible for the observed EL.

Keywords

III-V semiconductors; electroluminescence; gallium arsenide; gallium compounds; light emitting diodes; photoluminescence; semiconductor quantum dots; GaSb-GaAs; electroluminescence; light-emitting diode; photoluminescence; quantum dots; quantum rings; Atomic layer deposition; Gallium arsenide; Molecular beam epitaxial growth; Morphology; Quantum dots; Surface morphology; Surface treatment; GaSb quantum dots; light-emitting diode;

fLanguage

English

Journal_Title

Quantum Electronics, IEEE Journal of

Publisher

ieee

ISSN

0018-9197

Type

jour

DOI

10.1109/JQE.2010.2089041

Filename

5716917