Introducing Various BSF Materials and Different Doping Concentrations in Dual Junction Solar Cell with a View to Achieving Optimal Efficiency

An approach is developed in this paper based on introducing material variation on back surface field followed by varying emitter and base doping concentration in InGaP-GaAs dual junction solar cell. The analysis was carried out using a reference model of InGaP-GaAs solar cell with InGaAIP and AIGaAs as Back Surface Field (BSF) material of top and bottom cell respectively under AM 1.5 illumination. Initial approach began with fixed BSF layer of InGaAIP on top cell with several BSF material on bottom cell such as AIGaAs, InGaAs, InGaAIAs. Altering the primary assessment, the next inspection was done with fixed bottom cell BSF of InAIGaP and different BSF materials on top cell. The whole procedure was done by simulation method. Eventual evaluation was made on doping concentration of emitter and base layer of three selected cells succeeded by scrutinizing efficiency so far. For each of three cells an improved and higher efficiency is attained in a generalized way when emitter and base doping concentration was increased for top cell and decreased for bottom cell in a similar pattern in each cell and presented in the paper for InAIGaP _InAIGaP (from 34.65% to 35.28%), InAIGaAs_InAIGaP (from 35.5% to 36%) and AIGaAs_InAIGaP (from 36.32% to 36.79%).