PERFORMANCE
OF
COMPLETED
PROJECTS
STATUS REPORT
NUMBER 1
NIST SPECIAL PUBLICATION 950-1
Economic Assessment Office
Advanced Technology Program
Gaithersburg, Maryland 20899
William F. Long
Business Performance Research Associates, Inc.
Bethesda, Maryland 20814
March 1999
CONTENTS
Acknowledgements
Executive Summary
Introduction
CHAPTER 1 - Overview of Completed Projects
Characteristics
of the Projects
Timeline of Expected ATP Project
Activities and Impacts
Gains in Technical Knowledge
Dissemination of New Knowledge
Commercialization of the New Technology
Broad-Based Economic Benefits
CHAPTER 2 - Biotechnology
Aastrom
Biosciences, Inc.
Aphios Corporation
Molecular Simulations, Inc.
Thermo Trilogy Corporation
Tissue Engineering, Inc.
CHAPTER 3 - Chemicals and Chemical Processing
BioTraces,
Inc.
CHAPTER 4 - Discrete Manufacturing
Auto
Body Consortium (Joint Venture)
HelpMate Robotics, Inc.
PreAmp Consortium (Joint Venture)
Saginaw Machine Systems, Inc.
CHAPTER 5 - Electronics
Accuwave
Corporation
AstroPower, Inc.
Cree Research, Inc.
Cynosure, Inc.
Diamond Semiconductor Group, LLC
FSI International, Inc.
Galileo Corporation
Hampshire Instruments, Inc. (Joint Venture)
Illinois Superconductor Corporation
Light Age, Inc.
Lucent Technologies, Inc.
Multi-Film Venture (Joint Venture)
Nonvolatile Electronics, Inc.
Spire Corporation
Thomas Electronics, Inc.
CHAPTER 6 - Energy and Environment
American
Superconductor Corporation
Armstrong World Industries, Inc.
E.I. duPont de Nemours & Company
Michigan Molecular Institute
CHAPTER 7 - Information, Computers, and Communications
Communication Intelligence
Corporation #1
Communication Intelligence Corporation #2
Engineering Animation, Inc.
ETOM Technologies, Inc.
Mathematical Technologies, Inc.
Torrent Systems, Inc.
CHAPTER 8 - Materials
AlliedSignal, Inc.
Geltech Incorporated
IBM Corporation
APPENDICES
Appendix
A: Development of New Knowledge and Early Commercial Products
and Processes
Appendix
B: Terminated Projects
END NOTES
End Notes
Click here
for PDF version of report.
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Cree Research, Inc.
Processes for Growing Large, Single Silicon Carbide Crystals
| Most computer chips today
consist of tiny electrical and electronic components on a thin
slice of silicon crystal. As many as 5 million discrete components
can be placed on a piece of crystal less than 2 inches square.
Silicon crystal chips, however, are quite sensitive to heat.
Electricity passing through a chip's super-thin connecting wires
creates heat, just as it does in the heating element of a toaster.
If too much heat builds up, the chip loses its functionality. |
Beating the Heat in
Electronic Devices
This ATP project with Cree Research,
a small company in North Carolina's Research Triangle Park, made
significant progress in the development of an alternative raw material
for making crystal slices - silicon carbide. This material belongs
to a class of semiconductors having "wide bandgap," which means
they are relatively insensitive to increased temperatures. Silicon
carbide's thermal conductivity is greater than that of copper, so
it rapidly dissipates heat. It is impervious to most chemicals and
highly resistant to radiation. Silicon carbide is extremely hard
- it is used as grit in common sandpaper - indicating that devices
made with the substance can operate under extreme pressure. It also
possesses high field strength and high saturation drift velocity,
characteristics suggesting that devices made of it can be smaller
and more efficient than those made of silicon.
Cree and others have shown that, even
at red-hot temperatures, silicon carbide devices maintain functionality.
Some of them, in fact, have continued to operate at 650 degrees
Celsius. The wide bandgap also allows silicon carbide devices to
operate at shorter wavelengths, enabling the creation of blue light-emitting
diodes (LEDs) that could not be made from silicon. Moreover, full-color
LED displays become possible with the existence of blue LEDs, as
blue was a missing primary color.
Cree's LED chips used by Siemens A.G. for back lighting for this
dashboard.
The Real Color DisplayTM, a moving sign which is capable
of displaying the full range of colors, made possible by the use
of blue LEDs.
Growing Large Crystals
to Reduce Costs
Cree was founded in 1987 to commercialize
silicon carbide and began by making LEDs on a silicon carbide substrate.
Prior to its ATP project, Cree was already the world leader in silicon
carbide technology and had been making 1-inch-diameter silicon carbide
crystals. But progress in the development of devices based on silicon
carbide had been stymied by difficulties in growing large, high-quality
single crystals, a bottleneck that led Cree to pursue more research.
During the ATP project, Cree advanced
silicon carbide technology by developing methods to greatly reduce
the amount of imperfections in crystals and to increase their size
to two inches or greater in diameter. Larger-diameter crystals result
in lower production costs, which are crucial to opening markets
for silicon carbide devices. The company also developed ways to
significantly improve the doping (adding impurities to achieve desired
properties) and epitaxial deposition (growing one crystal layer
on another) processes for silicon carbide. Improving doping uniformity
directly increases production yield and thus reduces costs.
Cree's success with the ATP project
enables the fabrication of electronic devices that can operate at
much higher temperatures and withstand high power levels. Silicon
carbide components used in experimental high-definition television
(HDTV) transmission, for instance, delivered more power, lasted
longer and cost less to produce than conventional silicon-based
components. Now equipment that was costly to manufacture (owing
to the need for heat-dissipation systems) can be produced less expensively,
and devices that were impractical to make with pure silicon can
be made with silicon carbide.
New Products: Blue
LEDs and Silicon Carbide Wafers
The ATP project has been highly productive
for Cree and the economy at large. The company has used the new
technology to produce larger silicon carbide wafers to use in its
fabrication process for blue LEDs. It is also offering the larger
silicon carbide wafers for sale to other companies.
The low-cost blue light emitting diode (LED) produced with new
silicon carbide crystal technology.
Cree is using the ATP-funded technology
to reduce the cost of producing blue LEDs, and their sales have
increased substantially. Production cost is primarily a function
of the number of wafers processed. If wafer size can be increased
dramatically, the cost per device will decrease dramatically because
so many more devices can be made on a wafer. The silicon carbide
wafer technology is also aimed at markets for other blue light-emitting
optoelectronic devices, optical disk storage, microwave communications,
and blue and ultraviolet laser diodes, as well as high-temperature,
high-power and high-frequency semiconductors.
Benefits for the Economy
Benefits from the new silicon carbide
technology are already accruing to customers who have bought large
volumes of blue LEDs or silicon carbide wafers to use in their own
production. Performance measures (resistance, power output, sensitivity
to light, operating temperature) for silicon carbide devices are
frequently large, relative to available alternatives. Economic benefits
from these performance improvements spill over to other producers
involved in fabrication and assembly before a wafer-based product
reaches the end user. The total of these incremental benefits is
expected to be much larger than the profits Cree receives for selling
the silicon carbide wafers.
Cree's private success has led to public
benefit, which is expected to grow as the number of applications
for larger silicon carbide wafers increases. Westinghouse, for example,
used Cree's silicon carbide wafers in fabricating components for
the transmitter it used in the first commercial-level HDTV broadcast
in the United States, in 1996. Westinghouse said its transmitter
can deliver three times more power, has longer life and costs less
to produce than conventional silicon-based transmitters. Although
the number of HDTV transmitters that will use silicon carbide wafers
is unknown at this time, widespread use of this technology in HDTV
broadcasting could produce large general economic benefits if it
speeds commercialization of HDTV.
ATP Advantages
Cree reports it was attracted to the
ATP as a funding source for the development of the bulk crystal
and epitaxial growth technologies because the company could retain
its process technology knowledge. The ATP award also helped Cree
form alliances with research partners and speed the development
work, enabling the company to get results about 18 months sooner
than it would otherwise have been able to do. During the course
of its two-year ATP project, Cree also grew significantly.
Company officials say the success of
the ATP-funded project was primarily responsible for a subsequent
award of $5.8 million from the Defense Advanced Research Projects
Agency (DARPA) to further develop silicon carbide growth processes
to produce 3-inch wafers. If wafer size can be increased to 3 inches,
the cost per device will drop even further. This DARPA project got
under way in May 1995.
PROJECT:
To substantially reduce the cost and improve the durability
of light-emitting diodes (LEDs) and other electronic and optoelectronic
devices by increasing the quality and size (to 2 inches or more)
of silicon carbide (SiC) single crystals.
Duration: 6/15/1992 - 6/14/1994
ATP number: 91-01-0256
FUNDING (in thousands)::
| ATP |
$1,957 |
82% |
| Company |
435 |
18% |
| Total |
$2,392 |
|
ACCOMPLISHMENTS:
Cree essentially met or exceeded all of the technical milestones.
Successful development of the technology is indicated by the
fact that the company:
- applied for one patent on
technology related to the ATP project;
- presented several papers at
professional conferences;
- raised $13.2 million via an
initial public stock offering in February 1993;
- made high-quality, 2-inch
SiC wafers, greatly opening up the blue LED and SiC wafer
markets;
- raised approximately $17.5
million in a private stock offering in September 1995;
- increased annual revenues
from $3 million at the start of the ATP project in 1992
to $7.5 million at the end of the ATP award period in 1994;
- received $5.8 million from
the Defense Advanced Research Projects Agency in May 1995
for further development of silicon carbide growth processes
to support production of 3-inch wafers;
- formed Real Color Displays,
a wholly owned subsidiary, to exploit this technology for
full-color LED displays;
- received a $6 million order
in September 1996 from Siemens for blue LEDs; and
- supplied the SiC wafers for
components in the SiC solid-state transmitter used by Westinghouse
Electric to make the first U.S. commercial-scale high-definition
TV (HDTV) broadcast in April 1996.
COMMERCIALIZATION STATUS:
The larger SiC wafers, made with the ATP-funded technology,
are being used in the fabrication of blue LEDs sold to many
industrial customers. The wafers are also being provided in
limited quantities for development projects in government
and industry research laboratories.
OUTLOOK:
The improved processing technology makes the outlook for the
commercial use of SiC crystals highly promising. The cost
of producing blue LEDs has already been reduced substantially,
and the expected widespread commercial availability of larger-diameter
SiC wafers promises a new range of applications, including
HDTV transmitters. Benefits in the form of lower costs and
higher quality will accrue to industrial users of blue LEDs
and SiC wafers, as well as to consumers who use devices containing
these two Cree products.
COMPANY:
Cree Research, Inc.
2810 Meridian Parkway, Suite 176
Durham, NC 27713
Contact: Calvin Carter
Phone: (919) 361-5709
Number of employees:
41 at project start, 210 at the end of 1997
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Date created: March
1999
Last updated:
April 12, 2005
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