November 19, 2007

Katherine K. Martin 
Media Relations Office
216-433-2406
Katherine.k.martin@nasa.gov

RELEASE: 07-053

NASA TECHNOLOGY LICENSED FOR NEW PRESSURE SENSORS

Cleveland-Three patents covering high-temperature, harsh-environment 
silicon carbide pressure sensors have been licensed by NASA's Glenn 
Research Center to Endevco Corporation, San Juan Capistrano, Calif. 

The technologies include a packaging technique and chip fabrication 
methods that were developed by a team led by Dr. Robert Okojie at 
Glenn for use in aircraft engine combustion chambers. Silicon carbide 
(SiC) pressure sensors manufactured using these new processes can be 
used to improve testing of jet engines, in deep well drilling (where 
pressure and temperature increase as drilling depth increases), and 
in automobile combustion cylinders. 

Silicon carbide is used for these new technologies, rather than the 
traditional silicon, which eliminates the need for cooling and 
enables operation in extreme temperatures. Currently, SiC-based 
pressure sensors built using these NASA technologies are able to 
operate for 130 hours at 600 degrees Celsius in air, making it 
durable and reliable for use for the first time in engine ground 
testing and short duration flight test instrumentation. 

Glenn had used an Endevco silicon-based accelerometer in 2000 as a 
benchmark to validate Glenn's SiC accelerometer. Test results showed 
the NASA device operated as well as the Endevco benchmark device. 
However, NASA's SiC accelerometer had the added advantage of 
operating at much higher temperatures. This led to discussions 
between Endevco and Glenn about licensing opportunities to acquire 
Glenn's SiC pressure and accelerometer sensor fabrication and 
packaging technologies. 

As NASA's development of these new methods progressed, Endevco became 
interested in licensing the technology. After numerous visits to 
Glenn to see the technology first hand, a license to three patents 
was signed last month. Okojie will continue to work with Endevco to 
assist in overcoming any outstanding technical issues with the 
licensed technologies. 

According to Okojie, "Operation at high temperatures allows the SiC 
pressure sensors to be located in closer proximity to the sensed 
environment than conventional silicon based sensors, which must be 
isolated or protected in a water-cooled controlled environment. 
Placing the sensor closer to the harsh environment provides more 
reliable measurements. Additionally, its lighter weight due to 
absence of water-cooling plumbing makes the device less complex, 
relatively inexpensive and reduces tear-down cycle for engine 
maintenance. Its lightweight and reduced complexity leads to reduced 
engine weight for flight vehicles, hence improved fuel efficiency." 

"Endevco is very pleased to be afforded the opportunity to work with 
NASA on technology that has application in such a wide variety of 
industries," said Endevco President Scott W. Silcock. 

Endevco, a division of Endevco Corporation, a Meggitt group company, 
is a leading designer and manufacturer of dynamic instrumentation for 
vibration shock and pressure measurements. In 2006, the company 
expanded both the size and technical capabilities of its micro 
electro mechanical systems wafer fabrication facility in order to add 
controls and equipment to support advanced designs and enable high 
temperature and harsh-environment products. 

"The transfer of technology to industry is a significant part of 
NASA's heritage and charter," said Kathleen Needham, chief of Glenn's 
Technology Transfer and Partnerships office. "We actively pick 
companies such as Endevco which have the ability and desire to bring 
NASA innovation to market."

Okojie's work is a combined effort of the Aviation Safety and 
Fundamental Aeronautics programs under NASA's Aeronautics Research 
Mission Directorate. 

For more information on Glenn's silicon carbide electronics work, 
visit: 


http://www.grc.nasa.gov/WWW/SiC


For more information on NASA's Aeronautics Research Mission 
Directorate, visit:


http://www.aeronautics.nasa.gov

	
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