Thick Film Materials for Planar NOx (Nitrogen Oxide) Sensors
Ferro offers thick-film materials including platinum conductor pastes or inks and high temperature co-fireable ceramic tapes for use in planar NOx (Nitrogen Oxide) sensors.
EFFECTIVE NOx SENSOR CONSTRUCTION
Multiple layers of HTCC green tapes are implemented, and printed layers are formed using the screen-print technique to produce buried, insulated platinum heaters. All layers are co-fired at temperatures up to ~1550°C, using a correct product mix and prolonged firing regimes to ensure complete burn-out of the thick sensor build and to minimize blistering and warp.
Successful processing and firing of multilayer cofired structures used in NOx sensors requires knowledge of dimensional stability during layer build and printing, shrinkage during firing, and the necessary firing regime to ensure that flat, blister-free parts are produced.
The same manufacturing principles employed in the fabrication of oxygen sensors apply to the fabrication of NOx sensors, however, the product mix may be different and there may not be a need for a reference air channel as the measurement of NOx is not necessarily used to control Air Fuel Ratio (AFR).
Ferro has extensive experience in enabling the flat parts of planar NOx sensors to be constructed, even when using a combination of tapes and pastes.
We provide a range of materials that is suitable for the manufacture of the heater/electrode combination found in planar nitrogen oxide (NOx) sensors. The sensitive layer applied to the electrode is normally proprietary, however, Ferro offers paste-making services using customer-specified powders.
Our materials for sensor fabrication include platinum and zirconia pastes or inks. All Ferro materials for use in nitrogen oxide (NOx) sensor fabrication are manufactured to be lead-free, cadmium-free and phthalate-free. All of our HTCC inks and tapes used in planar NOx sensors are formulated to be RoHs and REACH compliant.
Ferro can also modify existing pastes and tapes to meet specific requirements or manufacture tapes and pastes from customer-supplied powders.
Lot sizes range from a few hundred grams to the high volumes required by the automotive industry.
THICK FILM MATERIALS FOR FOR PLANAR NOx (NITROGEN OXIDE) SENSORS
HIGH-TEMPERATURE CO-FIRED CERAMIC (HTCC) TAPES AND INK MATERIALS FOR PLANAR NITROGEN OXIDE (NOx) SENSORS
|FERRO PRODUCT||PRODUCT INFORMATION|
|4569 Porous Zirconia
|Porous zirconia paste used as a protective coating on
|4999-Q8 Porous Dielectric Paste||Used to control the rate of gas diffusion at the
|Platinum ink||5570 Platinum
|Conductive platinum paste used as a gas sensor
|Insulation ink||4530-B Alumina Dielectric Paste||Dielectric insulation ink used as the platinum heater
from the rest of the ceramic body
|PtRh ink||5724 Platinum-Rhodium Conductive Paste||Used as gas sensor electrode|
|Pt ink||5570 Platinum
|Used as gas sensor electrode|
|Terminal ink||5571 Platinum
|Platinum conductor used as a terminal pad for
|Heater ink||5574-A Platinum
|Platinum “resistor” for heater track to heat the
sensor to its operating temperature
|Via fill ink||5575 Platinum Conductive Via Fill
||Platinum via fill conductor used to interconnect
platinum layers through the zirconia ceramic body
|4443 Fugitive Paste||Fugitive paste used for making cavities in the fired
|Zirconia tape||42022-CWM Zirconia Ceramic Tape||Zirconica tape used as electrolyte as well as body of
the NOx sensor
|Glue ink||4431 Dielectric Paste||Glue ink used to facilitate lamination of the different
tape layers in the sensor
HTCC NOX SENSOR SYSTEM MATERIALS PRODUCT INFORMATION
VALUE ADDED SERVICES
Ferro has over 20 years of history in designing and manufacturing thick film materials and products formulated specifically for high temperature co-fired ceramics (HTCC) applications.
Successful processing and firing of multilayer co-fired structures utilized in NOx sensors requires knowledge of dimensional stability during layer build and printing, shrinkage during firing, and the necessary firing regime to ensure that flat, blister-free parts are produced. Our customers can leverage our prototype-building equipment and expertise in these processing aspects.
We also provide training at our own facilities or on-site at our customers’ locations, with comprehensive programs that cover most aspects of sensor manufacturing including materials, equipment, prototype building, testing and evaluation processes.