Thermionic generator

A thermionic generator for converting thermal energy to electric energy using thermal electrons displaced between a pair of an emitter electrode and a collector electrode, the thermionic generator comprising:

• the emitter electrode for emitting the thermal electrons from a thermal electron emitting surface of the emitter electrode when heat from an external heat source is applied to the emitter electrode;
• the collector electrode facing the emitter electrode and spaced apart from the emitter electrode by a predetermined distance, wherein the collector electrode receives the thermal electrons from the emitter electrode via a facing surface of the collector electrode, which faces the thermal electron emitting surface;
• and
• a substrate having one surface,
• wherein the emitter electrode and the collector electrode are disposed on the one surface of the substrate,
• wherein the emitter electrode is electrically insulated from the collector electrode, and
• wherein the thermal electron emitting surface and the facing surface are perpendicular to the one surface,
• wherein the emitter electrode and the collector electrode are made of semiconductor material with a semiconductor impurity, which is doped in the semiconductor material, respectively, and
• wherein a dopant concentration of the semiconductor impurity in the semiconductor material of the emitter electrode is higher than a dopant concentration of the semiconductor impurity in the semiconductor material of the collector electrode.

A thermionic generator for converting thermal energy to electric energy with using thermal electrons displaced between a pair of an emitter electrode and a collector electrode, the thermionic generator comprising:

• the emitter electrode for emitting the thermal electrons from a thermal electron emitting surface of the emitter electrode when heat from an external heat source is applied to the emitter electrode;
• the collector electrode receiving the thermal electrons from the emitter electrode via a facing surface of the collector electrode;
• an insulation layer sandwiched between the emitter electrode and the collector electrode;
• a substrate having one surface;
• and
• a pair of stacked structures, each of which includes the emitter electrode, the insulation layer and the collector electrode stacked on the one surface of the substrate,
• wherein the thermal electron emitting surface of the emitter electrode and the facing surface of the collector electrode in each stacked structure are disposed on a same plane,
• wherein the same plane of one stacked structure faces the same plane of the other stacked structure, and
• wherein the same plane of one stacked structure and the same plane of the other stacked structure are perpendicular to the one surface of the substrate.