| Popis: |
The fabrication of large-area solar cells (0.16 cm/sup 2/) on GaAs and AlGaAs structures with a new passivating coating, pyrolytic Si/sub 3/N/sub 4/, is demonstrated. Results in this study illustrate a near-oxide-free interface between GaAs and the Si/sub 3/N/sub 4/ coatings. These coatings were applied to three solar cell structures, a heteroface AlGaAs/GaAs cell, a graded band-gap AlGaAs cell, and a diffused homojunction cell. The results indicate that the pyrolytic Si/sub 3/N/sub 4/ coatings improve the surface (high energy) response of homojunction cells; however, they do not perform as well as cells with AlGaAs window layers on the surface. As a result, little improvement in the heteroface solar cell high-energy response was observed in this study. The best solar cells fabricated in this study with Si/sub 3/N/sub 4/ coatings were heteroface structures whose 1-sun, AMO conversion efficiencies were as high as 14.6%. |
