SIGNATURE WORK
CONFERENCE & EXHIBITION 2023

Thermophotovoltaic (TPV) cells transform infrared radiation to electricity by photoelectric effect and are promising in industries like high-power engines design. Germanium (Ge) is an ideal material for the TPV application because its low bandgap matches the infrared spectrum and the fabrication cost of Ge cells is relatively inexpensive. The purpose of this thesis is to 1) summarize the development of Ge cells for the past two decades, 2) propose and characterize a novel n‐GaInP2/p‐Ge heterojunction TPV cell, 3) implement an incremental conductance algorithm for maximum power point tracking (MPPT) of the fabricated TPV cell. The IV characteristic of the fabricated cell was measured by a source meter under different illuminations and fitted by a program, whose maximum power was also tracked by the incremental conductance algorithm in simulation. The maximum power generated and several fitted parameters of the fabricated TPV cell under the 1500 K illumination are at the medium level compared to previously reported Ge cells. The fabricated TPV cell has excellent VOC and JSC. To further improve the cell, thickness of the Ge substrate and design of the cell structure can be optimized. The implemented incremental conductance algorithm showed excellent tracking accuracy and stability with minor oscillation at maximum power point under normal operation condition. Heterojunction cells are intrinsically better than homojunction cells because heterojunction cells have improved collection efficiency of minority carriers and can reduce the production cost by allowing lower-quality film at the PN junction.