Solar cell performance as a function of emitter layer thickness and temperature

Abstract This work investigates the temperature-dependent performance of three homojunction solar cells composed of silicon, gallium arsenide, and indium phosphide, using the open-source simulation software PC1D. Emitter layer thicknesses ranging from 0.01 to 1 $$\upmu$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>μ</mml:mi> </mml:math> m were modeled across a temperature range of 273–373 K. The key photovoltaic parameters—short-circuit current density ( $$J_{\textrm{sc}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>J</mml:mi> <mml:mtext>sc</mml:mtext> </mml:msub> </mml:math> ), open-circuit voltage ( $$V_{\textrm{oc}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>V</mml:mi> <mml:mtext>oc</mml:mtext> </mml:msub> </mml:math> ), and conversion efficiency ( $$\eta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>η</mml:mi> </mml:math> )—were extracted to assess their thermal sensitivity. The results show that $$J_{\textrm{sc}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>J</mml:mi> <mml:mtext>sc</mml:mtext> </mml:msub> </mml:math> remains largely invariant with temperature, while $$V_{\textrm{oc}}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>V</mml:mi> <mml:mtext>oc</mml:mtext> </mml:msub> </mml:math> declines approximately linearly, driving the observed reduction in efficiency, $$\eta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>η</mml:mi> </mml:math> . Silicon exhibited the steepest thermal degradation, with $$\eta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>η</mml:mi> </mml:math> decreasing from 21.8 to 13.5%. GaAs and InP demonstrated greater thermal stability, with $$\eta$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>η</mml:mi> </mml:math> decreasing from 26.6 to 20.2% and 27.2 to 20.5%, respectively. Decreasing efficiencies were observed for all three cell configurations with increased emitter layer thickness. The greater temperature sensitivity of Si is attributed to stronger non-radiative recombination and phonon-assisted transitions characteristic of its indirect bandgap. Additional simulations on the impact of increasing surface recombination velocity and bulk carrier lifetime were carried out, indicating optimum performance at high lifetimes and low recombination velocities. These findings emphasize the advantages of direct bandgap materials for high-temperature photovoltaic applications and the efficacy of PC1D in explicating different material behaviors.