Simulation and Optimization of Silicon Solar Cell Back Surface Field

  • Souad TOBBECHE
  • Mohamed Nadjib KATEB
Keywords: BSF, electric field, optimization, silicon solar cell, TCAD Silvaco


In this paper, TCAD Silvaco (Technology Computer Aided Design) software has been used to study the Back Surface Field (BSF) effect of a p+ silicon layer for a n+pp+ silicon solar cell. To study this effect, the J-V characteristics and the external quantum efficiency (EQE) are simulated under AM 1.5 illumination for two types of cells. The first solar cell is without BSF (n+p structure) while the second one is with BSF (n+pp+ structure). The creation of the BSF on the rear face of the cell results in efficiency h of up to 16.06% with a short-circuit current density Jsc = 30.54 mA/cm2, an open-circuit voltage Voc = 0.631 V, a fill factor FF = 0.832 and a clear improvement of the spectral response obtained in the long wavelengths range. An electric field and a barrier of potential are created by the BSF and located at the junction p+/p with a maximum of 5800 V/cm and 0.15 V, respectively. The optimization of the BSF layer shows that the cell performance improves with the p+ thickness between 0.350.39 µm, the p+ doping dose is about 2 × 1014 cm-2, the maximum efficiency up to 16.19 %. The cell efficiency is more sensitive to the value of the back surface recombination velocity above a value of 103 cm/s in n+p than n+pp+ solar cell.