Abstract
In preparation for compliance with Califomia's SULEV standard and Euro STEP IV standard, which will take effect in 2002 and 2005, respectively, we have developed a laminated planar oxygen sensor. The developed sensor has the following characteristics: high thermal conductivity and superior dielectric characteristic, due to direct joining of the heater element alumina substrate and the sensor eIement zirconia electrolyte; low heat stress at temperature rise, due to optimized heater design; superior sensor protection from water droplets, and improved sensor response, due to optimized arrangement ofintake holes in the sensor cover. With these characteristics, the developed oxygen sensor can be activated in 10 seconds after cold start.
This report describes the technologies we used to develop the early-activation oxygen sensor.