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Mater Sci Nanotechnol 2017 | Volume 1 Issue 2
allied
academies
Nanomaterials and Nanochemistry
November 29-30, 2017 | Atlanta, USA
International Conference on
T
he development of wide-band gap compound
semiconductor materials and structures has been
led by the III-nitrides and they are fueling a revolution in
solid state lighting, solar cells, thermoelectric and other
applications. The talk will review many of the contributions
that the III-nitrides have made to date before focusing on the
development of InGaN for high temperature thermoelectric
materials and a new generation of high efficient solar
cells. Specifically, we will talk the various approaches to
increase thermoelectric efficiency of III-nitrides, including
electron quantum confinement, and phonon scattering to
increase the power factor and decrease the lattice thermal
conductivity. Additionally, high density-of-states (DOS) by
size reduction, resonant states by impurity doping, and
multi-valley band structure by band degeneracy have been
utilized to further enhance its figure of merit (ZT) value. The
impact of doping, and crystallographic defects on electrical
and thermal properties on the TE properties of nitride thin
films grown by metal organic vapor deposition (MOCVD) will
be systematically analyzed. Additionally, we will talk the III-
nitrides for a new generation of highly efficient solar cells. For
instance, InGaN with indium compositions up to 30% have
been developed for photovoltaic applications by controlling
defects and phase separation. InGaN solar cell design
involving a 2.9 eV InGaN p-n junction sandwiched between
p- and n-GaN layers yield internal quantum efficiencies as
high as 50%; while devices utilizing a novel n-GaN strained
window-layer enhanced the open circuit voltage. These
results establish the potential of III-nitrides in ultra-high
efficiency photovoltaics.
e:
luna@purdue.eduIll-nitrides: A universal semiconductor for energy applications thermoelectric and solar cells
Na Luna Lu
Purdue University, USA