All-top-contact 0.59 eV InGaAs thermophotovoltaic cells and modules

InGaAs cells are ideal converters for low temperature thermophotovoltaic power generation systems. Commonly, the positive and negative electrodes of InGaAs cells are deposited on the top and bottom of the cells, respectively. In the engineering of level modules, solder strips are used to connect the top and bottom of adjacent cells, the distance between the cells is considerable in order to prevent short circuits from the side wall of the cells, and the area ratio of cells to modules is relatively low. In this paper, we design and fabricate a novel all-top-contact InGaAs cell, with the positive electrode deposited on top of the p-InGaAs epitaxial layer, and the negative electrode deposited on top of the n-InPAs-grade epitaxial layer by precise etching of the p–n junction layers. The novel all-top-contact cells show good efficiencies compared to traditional cells with top-and-bottom electrodes under the same testing conditions. Novel flat and compact cell modules were fabricated using all-top-contact InGaAs cells, the distance between the adjacent cells was controlled within tens of microns, and the area ratio of cells to modules was improved efficiently.