Question

Problems-4: [3+2+2=7 pts] a) Consider a Si-solar cell with square cross-section with dimensions 2 cm x 2 cm, with thermalcurrent Ith= 32 nA (here thermal current is same as leakage

current) with an optical generation rateof 1018 EHP cm s' within Lp-Ln= 2 um of the junction. If the depletion width is 1 um, calculatethe short-circuit current and the open-circuit voltage for this cell. Also calculate the power expectedfrom the single cell of the fill factor is known to be 0.7. (EHP means electron hole pairs). b) Because Si-band gap is 1.1 eV, what is the cut-off wavelength for the photocurrent to be produced due to an incidence of light. c) Will light above or below this wavelength, produce photocurrent? Can sunlight produce a photocurrent for this solar-cell?

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