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Presents a study which described the optical and electrical characterization of high-efficiency silicon solar cells. Method of the study; Results and discussion; Conclusion.

A combination of electron paramagnetic resonance (EPR) and minority carrier lifetime measurements is used to unambiguously demonstrate that the presence of a B diffusion layer at the surface of oxidized Si (111) wafers causes a significant increase in the interface defect density as well as interface recombination, compared to undiffused surfaces. EPR measurements show a nearly three-fold increase in the Pb center density, while the lifetime measurements indicate an increase in surface recombination activity by a factor of more than two, for B diffused samples with a sheet resistance of ∼250 Ω/□□. [ABSTRACT FROM AUTHOR]

Several recent high performance silicon solar cells have taken advantage of surface oxide passivation to improve both their short wavelength response and open-circuit voltage. Using low resistivity substrates to minimize base recombination rates, the effect of oxidation conditions upon the passifying properties of thin oxides is quantified. It is shown that emitter recombination in high efficiency cells decreases by a factor of at least 3 and most probably 7 as the oxide growth temperature increases from 825 to 900 °C and the oxide thickness increases from 60 to 100 Å. This increase in performance is at the expense of a slight loss in cell short-circuit current density. [ABSTRACT FROM AUTHOR]

A new silicon solar cell structure, the passivated emitter and rear cell, is described. The cell structure has yielded independently confirmed efficiencies of up to 22.8%, the highest ever reported for a silicon cell. [ABSTRACT FROM AUTHOR]

Substantial improvements in silicon solar cell performance are reported. These improvements have been obtained primarily by improved cell open circuit voltage obtained by improved passivation of the cell emitter region. Careful attention to optical design and to the minimization of parasitic resistances has also resulted in the demonstration of short circuit current densities and fill factors comparable to the best values reported for silicon. [ABSTRACT FROM AUTHOR]