Open Access Nano Express

Growth of InAs Quantum Dots on Germanium Substrate Using Metal Organic Chemical Vapor Deposition Technique

Tanuj Dhawan1, Renu Tyagi2, RajeshKumar Bag2, Mahavir Singh2, Premila Mohan2, T Haldar2, R Murlidharan2 and RP Tandon1*

Author affiliations

1 Department of Physics & Astrophysics, University of Delhi, Delhi, 110007, India

2 Solid State Physics Laboratory, Lucknow Road, Timarpur, Delhi, 110054, India

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Citation and License

Nanoscale Research Letters 2009, 5:31-37  doi:10.1007/s11671-009-9439-y

Published: 19 September 2009

Abstract

Self-assembled InAs quantum dots (QDs) were grown on germanium substrates by metal organic chemical vapor deposition technique. Effects of growth temperature and InAs coverage on the size, density, and height of quantum dots were investigated. Growth temperature was varied from 400 to 450 °C and InAs coverage was varied between 1.40 and 2.35 monolayers (MLs). The surface morphology and structural characteristics of the quantum dots analyzed by atomic force microscope revealed that the density of the InAs quantum dots first increased and then decreased with the amount of InAs coverage; whereas density decreased with increase in growth temperature. It was observed that the size and height of InAs quantum dots increased with increase in both temperature and InAs coverage. The density of QDs was effectively controlled by growth temperature and InAs coverage on GaAs buffer layer.

Keywords:
Quantum dots; Ge substrate; InAs; Self-assembled