Numerical Study of the Effect of Temperature on the Performance of a Silicon Heterojunction Solar Cell (HIT) in the Presence of Excitons

In this article, a detailed study of the physical phenomena in the base of a silicon heterojunction solar cell (HIT) is elaborated. To carry out this work we have established a mathematical model which is in the form of a system of two continuity equations. The latter are subjected to physical conditions of nature to define our field of study. This system of continuity equations is solved using a computational program in a digital programming language. Numerical analysis is used in this study because the mathematical system describing the transport phenomena of load carriers (electrons and excitons) in a silicon heterojunction photovoltaic cell is very complex. Thus, to facilitate numerical resolution, the dimensional parameters of the physical system are rendered dimensionless. The resulting dimensionless equations are discretized by the finite volume method. They are then implemented in a calculation program by an iterative line-by-line relaxation method of the Gauss-Siedel type. In addition, with a low density coupling coefficient b=10-16cm3s-1 that depends on the material’s properties, the influence of temperature on the diffusion lengths, on the carrier and photocurrent densities, and on the internal quantum yield is studied. This study is carried out using polychromatic illumination with ultraviolet, visible and infrared wavelengths.