Molecular beam epitaxial growth of III-V semiconductor ... - KOBRA

Chapter 5
MBE Growth of Self-Assembled
InAs and InGaAs Quantum Dots
Embedded in Silicon Matrix
5.1 Overview
This chapter reports the experimental results of the growth and characterization
of self-assembled InAs and InGaAs quantum dots (SAQDs) embedded in a
silicon matrix on at silicon substrates. Key to this work is the study of the
silicon substrate preparation, including the investigation of dierent ex-situ (wet
etching with buer HF) and in-situ (thermal oxide desorption, Ga treatment
and atomic hydrogen cleaning (AH)) surface substrate treatments prior to MBE
growth. However, the homoepitaxy of a silicon buer layer after surface preparation
will create a freshly clean and smooth silicon surface for III-V heteroepitaxial
growth. The investigation of the inuence of InAs and InGaAs QDs growth parameters
such as (growth temperature, growth rate, nominal thickness and V/III
ratio) on their basic properties like density, size, shape, etc. and the systematic
structural and optical characterization is the core of this chapter. Investigation
of these parameters assists in identifying the origins of structural defects and suppressing
the formation of anti-phase domains, stacking faults and micro twins.
Careful calibration and optimization of the MBE growth parameters, as well as
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