Advances in Nano Research

Volume 2, Number 4, 2014, pages 211-217

DOI: 10.12989/anr.2014.2.4.211

Strain-induced islands and nanostructures shape transition\'s chronology on InAs (100) surface

Karen M. Gambaryan, Vladimir M. Aroutiounian, Arpine K. Simonyan, Yuanfei Ai, Eric Ashalley and Zhiming M. Wang

Abstract

The self-assembled strain-induced sub-micrometric islands and nanostructures are grown from In-As-Sb-P quaternary liquid phase on InAs (100) substrates in Stranski-Krastanow growth mode. Two samples are under consideration. The first sample consists of unencapsulated islands and lens-shape quantum dots (QDs) grown from expressly inhomogeneous liquid phase. The second sample is an n-InAs/p-InAsSbP heterostructure with QDs embedded in the p-n junction interface. The morphology, size and shape of the structures are investigated by high-resolution scanning electron (SEM) and transmission electron (TEM) microscopy. It is shown that islands, as they decrease in size, undergo shape transitions. Particularly, as the volume decreases, the following succession of shape transitions are detected: sub-micrometric truncated pyramid, {111} facetted pyramid, {111} and partially {105} facetted pyramid, completely unfacetted \"pre-pyramid\", hemisphere, lens-shaped QD, which then evolves again to nano-pyramid. A critical size of 5+-2 nm for the shape transformation of InAsSbP-based lens-shaped QD to nano-pyramid is experimentally measured and theoretically evaluated.

Key Words

strain-induced; pyramids; quantum dots; shape transition; III-V semiconductors

Address

Karen M. Gambaryan: Engineering Research Center for Semiconductor Integrated Technology, Institute of Semiconductors, Chinese Academy of Science, Beijing 100083, P.R. China; Department of Physics of Semiconductors and Microelectronics, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia Vladimir M. Aroutiounian: Department of Physics of Semiconductors and Microelectronics, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia Arpine K. Simonyan: Department of Physics of Semiconductors and Microelectronics, Yerevan State University, 1 Alex Manoogian St., Yerevan 0025, Armenia Yuanfei Ai: Engineering Research Center for Semiconductor Integrated Technology, Institute of Semiconductors, Chinese Academy of Science, Beijing 100083, P.R. China; Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P.R. China Eric Ashalley: Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P.R. China Zhiming M. Wang: Engineering Research Center for Semiconductor Integrated Technology, Institute of Semiconductors, Chinese Academy of Science, Beijing 100083, P.R. China; Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 610054, P.R. China