Chemistry Reference
In-Depth Information
10.4 Summary
We developed a method to form semiconductor nanodots on Si substrates by using
ultrathin Si oxide technology and reported some results on their electronic and opti-
cal properties. We could form ultrasmall semiconductor nanodots with the size of
∼
10
12
cm
−
2
on Si surfaces covered with ultrathin
5 nm and ultrahigh density of
∼
SiO
2
films of
3 nm thickness. We described electronic properties of the GeSn
nanodots on Si substrates and optical properties of Ge and GeSn nanodots embedded
in Si films, and those of GaSb nanodots on Si substrates. These structures exhibited
clear quantum confinement effects at room temperature and intense PL and EL
intensities in the energy region of about 0.8 eV that is of practical importance for
optical fiber communication systems.
We also reported that the ultrathin SiO
2
technology could be applied to grow thin
films on Si substrates even when the lattice mismatches between Si and thin films
were large.
∼
0
.
Acknowledgments
We would like to thank Dr. Y. Nakamura of Osaka University and Dr. A. A.
Shklyaev of The Institute of Semiconductor Physics, Novosibirsk, for their collaboration, and Prof.
N. Tanaka and Dr. S.-P. Cho of Nagoya University for scanning transmission electron microscope
observations. This work was partly supported by JSPS.KAKENHI (20360015).
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