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

Chapter 3
Heteroepitaxial Growth of III-V
Semiconductor on Silicon
Substrates
3.1 Overview
In order to realize the monolithic integration of III-V material on silicon substrate,
high-quality III-V compound layers should be grown on a Si substrate. However,
heteroepitaxy between III-V lms and silicon substrates induces a large strain
energy in the lms. Due to the large lattice and thermal mismatches, this large
strain is released by the formation of structural defects and dislocations in the
III-V material [1, 4]. The structural defects resulted from the heteroepitaxy are
closely related to carrier dynamics in the QDs and have severe inuence on their
optical quality. Therefore, the density of structural dislocations should be reduced
to an acceptable level or even defect-free structures as an ideal goal, since
the performance of light emitting devices is deteriorated and is degraded due
to the irradiative recombination processes occurring at defect centers. However,
structural-defect-free III-V compounds have not been grown on Si substrates by
lattice-mismatched heteroepitaxy regardless of a great deal of research [16, 3, 30].
The key challenges in the heteroepitaxy of semiconductors, relative to the development
of useful optoelectronic devices, are the control of the growth morphology,
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