Design of Ceramic Materials for Chemical Sensors with Intelligent Properties

1995 ◽  
pp. 719-725 ◽  
Author(s):  
Enrico Traversa
Keyword(s):  
Chemical Sensors ◽  
Ceramic Materials

Design of Ceramic Materials for Chemical Sensors: SmFeO3Thick Films Sensitive to NO2

1999 ◽  
Vol 82 (9) ◽  
pp. 2442-2450 ◽  
Author(s):  
Enrico Traversa ◽  
Stefano Villanti ◽  
Gualtiero Gusmano ◽  
Hiromichi Aono ◽  
Yoshihiko Sadaoka
Keyword(s):  
Chemical Sensors ◽  
Ceramic Materials

Packaging MEM Sensor Arrays

1999 ◽  
Vol 605 ◽  
Author(s):  
T. F. Marinis ◽  
D. A. Fulginiti ◽  
H. G. Clausen
Keyword(s):  
Chemical Sensors ◽  
Sensor Array ◽  
Dynamic Range ◽  
Low Cost ◽  
High Vacuum ◽  
Sensor Arrays ◽  
Ceramic Materials ◽  
Leakage Rate ◽  
Single Chip ◽  
Sensor Package

AbstractMany applications of MEM sensors require hermetic or high vacuum packaging of sensor clusters. For example, multiple gyroscopes or accelerometers are fabricated on a single chip to improve alignment and stability of input axes or increase the dynamic range of instruments. Chemical sensors are fabricated as large arrays to both improve selectivity and increase the number of species that can be detected. Still larger arrays of sensors must be packaged for hydrophone and bolometer imaging devices. All of these applications place a demanding combination of requirements on the sensor package. The electrical outputs of the sensor array must be well isolated from each other as well as power and excitation signals, while parasitic capacitance is minimized. The package must also be capable of being evacuated and sealed to achieve a pressure of 5 millitorr with a leakage rate below 10−11 [Std cc sec−l]. Finally, the package must be compact and low cost to realize these same attributes of the MEM sensor. This paper describes a packaging approach that is based on low temperature cofired ceramic materials. This technology meets the packaging requirements of sensor arrays and is well suited to the research environment in which the sensor design is continually evolving.

Design of Ceramic Materials for Chemical Sensors: Effect of SmFeO3 Processing on Surface and Electrical Properties

2004 ◽  
Vol 84 (2) ◽  
pp. 341-47 ◽  
Author(s):  
Hiromichi Aono ◽  
Masaki Sato ◽  
Enrico Traversa ◽  
Masatomi Sakamoto ◽  
Yoshihiko Sadaoka
Keyword(s):  
Electrical Properties ◽  
Chemical Sensors ◽  
Ceramic Materials

Examination of Fracture Interfaces in Silicon Nitride

1975 ◽  
Vol 33 ◽  
pp. 60-61
Author(s):  
Nancy J. Tighe
Keyword(s):  
Silicon Nitride ◽  
Grain Boundary ◽  
Crack Growth ◽  
Subcritical Crack Growth ◽  
Slow Crack Growth ◽  
Ceramic Materials ◽  
Grain Boundary Sliding ◽  
Boundary Phase ◽  
Turbine Engines ◽  
Boundary Sliding

Silicon nitride is one of the ceramic materials being considered for the components in gas turbine engines which will be exposed to temperatures of 1000 to 1400°C. Test specimens from hot-pressed billets exhibit flexural strengths of approximately 50 MN/m2 at 1000°C. However, the strength degrades rapidly to less than 20 MN/m2 at 1400°C. The strength degradition is attributed to subcritical crack growth phenomena evidenced by a stress rate dependence of the flexural strength and the stress intensity factor. This phenomena is termed slow crack growth and is associated with the onset of plastic deformation at the crack tip. Lange attributed the subcritical crack growth tb a glassy silicate grain boundary phase which decreased in viscosity with increased temperature and permitted a form of grain boundary sliding to occur.

Sign in / Sign up

Export Citation Format

Share Document