SiC jet engine sensors prepare for take-off
Endevco is lining itself up as the first commercial manufacturer of SiC MEMS sensors for high-temperature environments like jet engines, turbines and oil drills.
The technology comes courtesy of three patents that Endevco bought from NASA in October and has subsequently been learning how to deploy.
“We ve licensed a breakthrough development - right now these sensors aren t commercially available,” explained Jennifer MacDonell, general manager of Endevco's Sunnyvale, California, MEMS manufacturing operations.
Having now studied the NASA process, Endevco is looking to obtain the equipment needed to reach its target of producing the MEMS devices by 2010.
At that point the company hopes to be selling thousands of MEMS pressure sensors annually, although it will provide prototypes to key customers in 2009.
The patented MEMS "“ micro electrical mechanical systems "“ take advantage of the piezoresistance of n-type SiC that causes changes in current flow when the material is mechanically deformed.
By suspending a “proof” mass above the n-type SiC layer that can press down onto it, devices can be made that convert changes in pressure and acceleration into measurable resistance changes.
This is analogous to the silicon MEMS that Endevco already manufactures, however the hardier SiC can be used to make sensors that will provide crucial data at higher temperatures. Currently, NASA s SiC pressure sensors operate for 130 hours at 600°C in air.
“Silicon carbide also has the ability to withstand chemically harsh environments,” MacDonell added, “so once we've tackled the applications we've targeted, we can see what else to take.”
In the meantime pressure sensors for jet engines are the main aim of Endevco s development efforts, and aerospace is also likely to be the first market in which its accelerometers will be employed.
