Thermoresistive heating plate for microwave appliance

A thermoresistive heating plate for a combination microwave oven, the thermoresistive heating plate comprising:

• a substrate having a first surface configured to form a portion of an interior of a cooking chamber, and a second surface opposite to the first surface;
• and
• a thermoresistive coating including a ceramic coating matrix with conductive filler particles dispersed therein, the thermoresistive coating disposed on at least a portion of the second surface and the conductive filler particles configured to generate heat upon application of an electric current,
• wherein the heat is conductible through the substrate from the thermoresistive coating into the cooking chamber, and the substrate is transparent to microwave radiation to allow microwave emission through the substrate into the cooking chamber.

A method of forming a heating appliance comprising:

• providing a housing having interior walls with interior surfaces defining a cooking chamber for heating food;
• applying a thermoresistive coating to a surface of a substrate to form a thermoresistive heating plate, the thermoresistive coating including a ceramic coating matrix with conductive filler particles dispersed therein, the conductive filler particles configured to generate heat upon application of an electric current;
• and
• positioning the thermoresistive heating plate in an opening defined in an interior wall such that microwave radiation can pass through the substrate into the cooking chamber,
• wherein an inner surface of the substrate, opposite to the bottom surface, is flush with the interior surface of the interior wall to define the cooking chamber.