High-Yield Manufacturing of Thin Solar Cells via Reduced-Handling Process

Cells can reach 24% efficiency Higher manufacturing yield Lower production cost

Solar energy

This new three-step approach to fabricating thin heterojunction solar cells is based on direct Si-Si bonding. The method applies to HIT (heterojunction intrinsic thin layer) and SHJ-IBC (silicon-heterojunction interdigitated-back-contact) cells, which, when well below 100 ╬╝m thick, can reach efficiencies beyond 24%. Other prevalent cell types like PERC and selective emitter reach no more than 22% efficiency. By fully processing transparent substrates as building blocks, solar cells fabricated this way can be as thin as 20 ╬╝m with correspondingly high efficiency. Beginning with two glass substrates, the method calls for depositing a transparent conductive oxide, amorphous silicon, and intrinsic amorphous silicon, in succession. The thin crystalline silicon wafer is then sandwiched between two essentially processed transparent substrates and bonded to both substratesΓÇÖ amorphous silicon layers. A go-to approach in the MEMS (microelectromechanical systems) industry, Si-Si bonding can also benefit the PV industry by simplifying solar cell manufacturing through this new method.

USA