Physical Review B 72, 115337 (2005)
| Roughness-induced piezoelectric charges in wurtzite group-III-nitride heterostructures | |
| Roughness-induced piezoelectric charges in wurtzite group-III-nitride heterostructures | |
| Tạp chí Physical Review B 2005 27 September 2005; 72 (11):115337 | |
| Tác giả | Doan Nhat Quanga, Nguyen Huyen Tungb, Vu Ngoc Tuocb, Nguyen Viet Minhb and Pham Nam Phongb |
| Nơi thực hiện |
a
Center
for
Theoretical
Physics,
Vietnamese
Academy
of
Science
and
Technology,
P.O.
Box
429,
Boho,
Hanoi
10000,
Vietnam
bInstitute of Engineering Physics, Hanoi University of Technology, 1 Dai Co Viet Road, Hanoi, Vietnam |
| Từ khóa | piezoelectric, strain relaxation, heterostructures, wurtzite structure |
| DOI URL PDF | |
Abstract[sửa]
We
present
a
theoretical
study
of
the
disorder
effect
due
to
interface
roughness
on
piezoelectricity
in
wurtzite
group-III-nitride
heterostructures,
e.g.,
AlGaN/GaN.
We
have
proved
that
interface
roughness
gives
rise
to
random
nonuniform
fluctuations
in
the
piezoelectric
polarization.
As
a
result,
besides
the
uniform
density
of
sheet
piezoelectric
(and
spontaneous)
polarization-induced
charges
on
the
interface,
reported
in
the
existing
literature,
there
must
exist
fluctuating
densities
of
bulk
piezoelectric
charges
inside
of
both
the
strained
and
relaxed
layers
as
well
as
a
fluctuating
density
of
sheet
piezoelectric
charges
on
the
interface.
The
densities
of
these
charges
and
their
electric
field
were
generally
found
to
be
high.
The
maximal
rms
density
of
roughness-induced
bulk
charges
may
be
so
large
as
,
while
the
rms
density
of
roughness-induced
sheet
charges
may
be
of
the
order
of
magnitude
of
the
uniform
density
of
sheet
piezoelectric
charges,
up
to
.
Thus,
the
effects
of
piezoelectric
polarization
on
the
conductivity
in
actual
wurtzite
group-III-nitride
heterostructures
turn
out
to
be
counteracting,
namely
as
a
source
of
making
up
the
two-dimensional
electron
gas,
but
also
as
a
source
of
their
scattering.
