InAs nanostructures on GaAs

  • Itaru Kamiya Quantum Interface Laboratory, Toyota Technological Institute

Abstract

InAs on GaAs provides an opportunity to prepare unique devices due to 1) the narrow bandgap of InAs, 2) different surface Fermi-level location, and 3) lattice mismatch. Historically, while InAs was an attractive material for realizing surface two-dimensional electron gas or optoelectronic devices that works in the infrared, its incorporation into Si or GaAs based structures was found to be a difficult task. However, the situation changed after people realized that the non-planar structures that form upon epitaxial growth by molecular beam epitaxy (MBE) or metal-organic chemical vapor deposition (MOCVD), due to the 7% lattice mismatch, could be used as quantum dots (QDs). This occurs through a process known as Stranski-Krastanov (SK) mode, where the initial InAs layer grown on GaAs(001) is strained, but sustain a planar structure, but convert into three-dimensional (3D) structure when the total deposition exceeds what is called the "critical thickness" (1.7 monolayer in this case). The SK QDs have been extensively studied, and today, lasers, photodetectors/sensors, solar cells, etc., are realized using InAs QDs. Nevertheless, since the SK growth is a self-organizing process, limitation remains in the control of the QD size, morphology, and consequently the optical and electronic properties. Further, we have addressed that for the application of the so-called interband solar cells, disk-like shaped structures, which we call the quantum well islands (QWIs) could be advantageous over QDs. We have been investigating both the control and mechanisms of InAs nanostructure growth on GaAs(001). In the present talk, we would like to provide an overview together with some of our latest results.

About the Speaker

Itaru Kamiya was born in Kyoto, raised mostly in the Tokyo Metropolitan area. He spent part of his younger days in Los Angeles, U.S.A, Brussels, Belgium, and Sussex, UK. He received his BS, MS, and PhD in Applied Physics from the University of Tokyo. After receiving his PhD, he joined RIKEN, Japan, as a Special Basic Scientist. Subsequently, he joined Bellcore, NJ, USA, officially appointed by the University of Illinois, as a Research Physicist. He then worked as a JRDC Research Fellow at Imperial College, London, and also at RCAST, University of Tokyo.

He then joined Mitsubishi Chemical Corporation, Yokohama, Japan, as a Research Scientist, later led the Nanotechnology Laboratory as the manager. He has been a professor at the Toyota Technological Institute, Nagoya, Japan, since 2004. His interest lies in the crystal growth and optoelectronic properties of semiconductor nanostructures and related materials, with focus on surface and interface properties.

Published
2020-02-09
How to Cite
[1]
I. Kamiya. InAs nanostructures on GaAs, Proceedings of the Samahang Pisika ng Pilipinas 38, SPP-2020-INV-5B-01 (2020). URL: https://paperview.spp-online.org/proceedings/article/view/SPP-2020-INV-5B-01.