Abstract: A ceramic heater for a DC power source comprising an insulating ceramic sintered body, a heating resistor composed of at least two separate layers of heating resistor made of an inorganic conductive material, leads made of high-melting point metal wires and connected to each end of the layers, and electrodes made of an inorganic conductive material, each formed in a single layer or divided into a plurality of pieces and connected to the leads, the heating resistor, leads and electrodes being embedded in the ceramic sintered body.The present invention further includes six related inventions closely related with one another in regard to the above-mentioned ceramic heater and ceramic glow plugs embodied by using the ceramic heater.

Abstract: A ceramic heater having a ceramic substrate, a heat-generating resistor disposed in the interior of the ceramic substrate or on the surface of the ceramic substrate and terminals connected to both the ends of the heat-generating resistor, wherein the ceramic substrate is composed of a sintered body of a nitride of an element selected from the group consisting of silicon and aluminum and the heat-generating resistor is composed of a ceramic layer containing titanium nitride (TiN) or tungsten carbide (WC).