Multijunction Solar Cell Substrate

Germanium has long been a popular material for integrated circuits.

Multijunction solar cell substrate.

Recently devel oped thin lm iii v solar cells based on exible substrates represent an attrac. High efficiency multijunction devices use multiple bandgaps or junctions that are tuned to absorb a specific region of the solar spectrum to create solar cells having record efficiencies over 45. 1 inverting the usual growth order growing mismatched cells last 2 engineering a transparent buffer layer to mitigate dislocations and 3 removing the primary substrate attachment to the secondary handle. Multi junction mj solar cells are solar cells with multiple p n junctions made of different semiconductor materials each material s p n junction will produce electric current in response to different wavelengths of light the use of multiple semiconducting materials allows the absorbance of a broader range of wavelengths improving the cell s sunlight to electrical energy conversion efficiency.

Multi junction solar cells and methods for making multi junction solar cells are disclosed. Back contact only multi junction solar cells having recessed through substrate vias wherein the side facing the sun is capable of withstanding environments for use in space are disclosed. The maximum theoretical efficiency that a single bandgap solar cell can achieve with non concentrated sunlight is about 33 5 primarily because of. Monolithic integration of iii v compound semiconductors on si substrates is of major importance for next generation electronics optoelectronics and photovoltaic devices for energy conversion the successful integration of these lattice mismatched semiconductors would result in a significant cost reduction of multijunction solar cell due to the combined lower cost of.

The device has a very high conversion efficiency of approximately 40 and high open circuit voltage and low series resistance. Iii v solar cell structures are conventionally grown on thick single crystalline semiconductor substrates which signi cantly inhibit the mechanical exibility of the solar cells and limit their speci c power per weight 5. Solar cells with efficiencies higher than 30 including multijunction iii v cells and iii v cells combined with silicon cells are the best candidates for applications in the automotive sector. A solar cell is disclosed with v grooves which are series connected but electrically isolated indirect bandgap solar cells which are responsive to different light frequencies on both sides of a semi insulating optically transparent substrate.

A promising platform for multi junction solar cells.