Biomedical Engineering Reference
In-Depth Information
Fig. 2.18
Octa-QDMs can encode more logic values of 1, 0, and 1/2 for extended quantum dot
cellular automata (EQCA) application
2.7
Summary
In this presentation, we intensively study the droplet epitaxial growth of InP
ring-shaped QDMs. The quantum nanostructure is created on In0.5Ga0.5P/GaAs
substrate based on the combination of droplet epitaxy technique for QR formation
and strain-driven mechanism due to lattice mismatch between InP and In0.5Ga0.5P
for QD formation on the ring robe when the critical thickness of indium coverage is
reached.
Based on the AFM observation together with TEM confirmation and the exper-
imental results on photoluminescence of the InP ring-shaped QDMs, we optimize
the growth parameters as follows: the deposition and crystallization temperatures
at 250 and 200
◦
C with indium deposition rate of 1.6 ML/s and indium thickness
of 3.2 ML. The QDMs with eight QDs per ring are our target in the fabrication
which has a potential application in EQCA. The percentage of these ring-shaped
octa-QDMs at the optimized growth condition is about 46%.
Acknowledgments
This research article is an output which is supported by Thailand Research
Fund (TRF) and Office of High Education Commission (OHEC) of Thailand in combined projects,
i.e. Senior Research Scholar (RTA5080003), Distinguished Professor Grant (DPG5380002),
the Royal Golden Jubilee Ph.D. program (Grant No. PHD/0040/2549). This research work is
also supported by the Higher Education Research Promotion and National Research University
Project of Thailand, Office of the Higher Education Commission (EN1180A-55) as well as by
Nanotechnology Center of Thailand with counterpart fund from Chulalongkorn University.
