Nanopatterning and bandgap grading to reduce defects in CdTe solar cells

摘要: We present simulation and experimental results proving the feasibility of a novel concept to increase efficiency CdTe based solar cells. In order achieve $0.50/W price in modules, higher efficiencies need be attained. The high defect density due lattice-mismatch between CdS reduces lifetime, voltage, propose use graded composition structure patterned substrate reduce defects, Innovative simulations using high-fidelity molecular dynamics predict that defect-free films are possible if film is with Zn constructed as nano-islands sizes below 90 nm. Both stresses. Also, creates back surface field an enhanced ohmic contact. have attempted grow ZnTe on substrates template micro nano-islands. Selective growths shown fewer grain boundaries when island size decreases 300 larger were obtained CdTe/ZnTe stack compared single layer CdTe. demonstrate for first time ability nanopatterned enhance uniformity thin