Patent ID: 8362400
Filing Date: 2013-01-29
Classification: C04B,G01N

Abstract:
1. A ceramic joining unit, comprising: a ceramic base member having a leading end side and a rear end side, said ceramic base member extending in a longitudinal direction; an electrode pad formed of at least one of tungsten and molybdenum, as a main component thereof, provided on a surface of the ceramic base member; a coupling terminal for electrical connection to an external circuit; and a joining portion which joins the electrode pad to the coupling terminal by means of a solder joint, wherein the electrode pad includes: wherein each of the first layer and the second layer contains a ceramic material as a main component among ceramic materials forming the ceramic base member, a content (wt %) of the ceramic material in the first layer is greater than a content (wt %) of ceramic material in the second layer, and a contour of the upper surface of the first layer is located outside of a contour of the bottom surface of the second layer at an entire periphery of the first layer.