Multi-junction solar cell with a dilute nitride subcell having a slope doping

摘要

By having an exponential doping, lattice matching solar cell with a dilute nitride sub-cell, controls the current capacity of the solar cell. Specifically, a solar cell with a dilute nitride subcell at least one with a base or an emitter doped variably are disclosed. In one embodiment, lattice-matched multi-junction solar cell has an upper subcell and a lower subcell dilute nitride and middle subcell has a doping in the emitter and base and / or dilute nitride bottom subcell, which is , and that is partially doped exponentially at least, to improve the performance characteristics of the multi-junction solar cells. In the structure, dilute nitride subcell has the lowest band gap, it is possible to lattice match to the substrate, typically, the intermediate cell has a higher bandgap than the dilute nitride subcells , on the other hand, it is lattice-matched to dilute nitride subcell. Typically, has the highest band gap, the top subcell is lattice-matched to the adjacent subcell. In another embodiment, four, sometimes having a subcell 5 or more subcells s 1 if the multijunction solar cell according to the present invention, dilute nitride which is doped exponentially I each comprise things alloy. [Selection Figure Figure 5