- Email: [email protected]
Step-free wide-bandgap heteroepitaxy
Step-free wide-bandgap NASA’s Glenn ReXarch
heteroepitaxy
Center
fdms by flattening
(Cleveland, OH, USA) led by Philip Neudeck
hexagonal
- together with
scientists
from Ohio Aerospace
Institute
(Cleveland, OH, USA)
by changing temperature nucleation
have described throughs
NY, USA)
a
The films formed were free
-
both of defects propagated
two break-
from the substrate
that may enable more
reliable wide-bandgap
and
rate, depositing
thin film of cubic 3CSiC.
and the State University of New York (Stony Brook,
mesas of
4H- or 6H-Sic then,
and of pla-
nar defects, i.e. in the order
devices: SEM of thin lateral W-X cantilever emanating from mesa top after 30 minutes of growth. (Courtesy NASA Glenn)
(stacking
wafers by creating a pattern of
ing from adjacent legs grew
crystal nucleation
square, device-size
together to form a web cover-
stages is the likely cause of pla-
ing the area between
nar defects,” said Neudeck.
l
In 2000 the team announced
a web growth process
which
extends the size of atomically flat (or step-free)
commercial
mesas on
“For cubic SIC films, too rapid
the legs
ing the steps on those mesas to
and producing
the edges.
flat surface larger than the orig-
Unexpectedly
the crystals grew
laterally beyond the mesa edges and formed thin cantilevers overhanging
the sidewalls. For
open-geometry and crosses)
mesas (e.g. vees cantilevers
extend-
bound-
aries) of crystal planes.
areas on Sic
wafers, then grow-
faults) or alignment
(double positioning
an atomically
The team will use step-free surface heteroepitaxy
inal mesa (and possibly over areas containing
in the early
wide-bandgap
inherent
with other
films on hexago-
nal Sic to investigate
defects).
the feasi-
bility of industrial fabrication
More recently they created
a wider range of much
step-free surface heteroepitaxy,
improved wide-bandgap
l
eliminating
of
devices.
defects in deposited
__
More precise crystal growth university of
from one crystalAs
wisconsin-
Madison Materials Science Engineering
professor
and
Sindo
Kou ([email protected])
and
bottom of the crucible
a crystal
grows, it rejects impurities
into
holds a
solid material identical in com-
the melt, so the melt composi-
position
tion and therefore
the upper part holds the melt.
crystal com-
graduate student Jia-Jie He have
position
devised a method to ensure
They first lengthened
can change.
to the desired crystal;
As the crystal grows and the the cru-
melt level decreases,
an existing
cible in which the materials
mechanism
the growth of single-crystal
melt then added a low-tempera-
upward so that the solid materi-
alloy semiconductors
ture heater around the cru-
al gradually enters the high-
stant along its length, avoiding
cible’s lower half and moved
temperature
inconstencies
in performance
the existing high-temperature
and keeps the melt composi-
of devices made from wafers
heater to the upper halfThe
tion constant.
that the melt composition
in
stays con-
_____._.____-_._-__~--
pushes the crucible
heat zone, melts
----
3 inch Sic substrates Uniroyal Technology
Cooperative
pling 3” 6H-polytype
DAAD17-0O-C-0111).
semi-insulating Research
ADVANCED
SEMICONDUCTOR
expansion
3” 4H-polytype
semiconducting connection
SIC semi-
Laboratory
Contract/
Agreement
number
substrates.
by developing
’ ‘I
and US Army
Inc (Sarasota, FL, USA) is sam-
It plans to continue
REVIEW
F33615-99-C-5317 Research
conducting
Ill-Vs
Corp sub
sidiary Sterling Semiconductor
substrates substrates
and (in
with US Air Force Laboratory
MAGAZINE
Contract
VOL 15 - NO I
Sterling recently
extended
its
the expansion business
of semi-insulating
substrates.
pleted the sale of its Specialty Adhesives
segment
~~$2I.bm
- “another step in
for about
assets into the Compound for
of its Sic wafer
and its development
Corp
(Sarasota, FL, USA) has com-
the re-deployment of our
leases on its facilities in Danbury, CT and Sterling,VI,
* Uniroyal Technology
Semiconductor and Optoelectronics business segment,” says chairman Howard R Curd.
and CEO
heteroepitaxy
Center
fdms by flattening
(Cleveland, OH, USA) led by Philip Neudeck
hexagonal
- together with
scientists
from Ohio Aerospace
Institute
(Cleveland, OH, USA)
by changing temperature nucleation
have described throughs
NY, USA)
a
The films formed were free
-
both of defects propagated
two break-
from the substrate
that may enable more
reliable wide-bandgap
and
rate, depositing
thin film of cubic 3CSiC.
and the State University of New York (Stony Brook,
mesas of
4H- or 6H-Sic then,
and of pla-
nar defects, i.e. in the order
devices: SEM of thin lateral W-X cantilever emanating from mesa top after 30 minutes of growth. (Courtesy NASA Glenn)
(stacking
wafers by creating a pattern of
ing from adjacent legs grew
crystal nucleation
square, device-size
together to form a web cover-
stages is the likely cause of pla-
ing the area between
nar defects,” said Neudeck.
l
In 2000 the team announced
a web growth process
which
extends the size of atomically flat (or step-free)
commercial
mesas on
“For cubic SIC films, too rapid
the legs
ing the steps on those mesas to
and producing
the edges.
flat surface larger than the orig-
Unexpectedly
the crystals grew
laterally beyond the mesa edges and formed thin cantilevers overhanging
the sidewalls. For
open-geometry and crosses)
mesas (e.g. vees cantilevers
extend-
bound-
aries) of crystal planes.
areas on Sic
wafers, then grow-
faults) or alignment
(double positioning
an atomically
The team will use step-free surface heteroepitaxy
inal mesa (and possibly over areas containing
in the early
wide-bandgap
inherent
with other
films on hexago-
nal Sic to investigate
defects).
the feasi-
bility of industrial fabrication
More recently they created
a wider range of much
step-free surface heteroepitaxy,
improved wide-bandgap
l
eliminating
of
devices.
defects in deposited
__
More precise crystal growth university of
from one crystalAs
wisconsin-
Madison Materials Science Engineering
professor
and
Sindo
Kou ([email protected])
and
bottom of the crucible
a crystal
grows, it rejects impurities
into
holds a
solid material identical in com-
the melt, so the melt composi-
position
tion and therefore
the upper part holds the melt.
crystal com-
graduate student Jia-Jie He have
position
devised a method to ensure
They first lengthened
can change.
to the desired crystal;
As the crystal grows and the the cru-
melt level decreases,
an existing
cible in which the materials
mechanism
the growth of single-crystal
melt then added a low-tempera-
upward so that the solid materi-
alloy semiconductors
ture heater around the cru-
al gradually enters the high-
stant along its length, avoiding
cible’s lower half and moved
temperature
inconstencies
in performance
the existing high-temperature
and keeps the melt composi-
of devices made from wafers
heater to the upper halfThe
tion constant.
that the melt composition
in
stays con-
_____._.____-_._-__~--
pushes the crucible
heat zone, melts
----
3 inch Sic substrates Uniroyal Technology
Cooperative
pling 3” 6H-polytype
DAAD17-0O-C-0111).
semi-insulating Research
ADVANCED
SEMICONDUCTOR
expansion
3” 4H-polytype
semiconducting connection
SIC semi-
Laboratory
Contract/
Agreement
number
substrates.
by developing
’ ‘I
and US Army
Inc (Sarasota, FL, USA) is sam-
It plans to continue
REVIEW
F33615-99-C-5317 Research
conducting
Ill-Vs
Corp sub
sidiary Sterling Semiconductor
substrates substrates
and (in
with US Air Force Laboratory
MAGAZINE
Contract
VOL 15 - NO I
Sterling recently
extended
its
the expansion business
of semi-insulating
substrates.
pleted the sale of its Specialty Adhesives
segment
~~$2I.bm
- “another step in
for about
assets into the Compound for
of its Sic wafer
and its development
Corp
(Sarasota, FL, USA) has com-
the re-deployment of our
leases on its facilities in Danbury, CT and Sterling,VI,
* Uniroyal Technology
Semiconductor and Optoelectronics business segment,” says chairman Howard R Curd.
and CEO