Improved dislocation model of silicon solar cells with the effect of front and back surface recombination velocity

Abstract

We have extended a previous model for calculating the effects of dislocations on the characteristics of a Si solar cell to include the effects of front and back surface recombination. This improved dislocation model uses Green's function approach to solve the three‐dimensional continuity equation of the minority carriers with suitable boundary conditions corresponding to surface recombination at the n and p sides. The dislocations are considered to be localized lines, extending perpendicular to the front and back surfaces of the cell and having a recombination velocity. We discuss effect of several parameters such as bulk dislocation density, minority carrier diffusion length in p and n regions on the J‐V characteristics, and spectral response of the cell. It is shown that these results agree well with previously published, experimental data. Copyright © 2013 John Wiley & Sons, Ltd.

Effect of SiO2 and SiNx Passivation on CdTe based Solar Cells

“…The deposition of SiO 2 reduces the surface recombination and enhances the performance of solar cells. The effect of back surface recombination cannot be neglected in CdTe solar cells because of the less thickness of solar cells [12].…”

Simulation of device parameters of high efficiency multicrystalline silicon solar cells

“…The role of back surface recombination velocity will be signifi cant if the wafer gets thinner. The change in spectral response with respect to S 2 will be more pronounced (Budhraja et al, 2011c) when the thickness of the cell is further reduced by the solar cell industry. This is because of the fact that, in thinner wafers, the generation rate will be signifi cant at the back surface and can no longer be neglected.…”

Dislocation contrast in cathodoluminescence and electron-beam induced current maps on GaN(0 0 0 1)

“…Taking t sufficiently large, we arrive at the solution for the half-space. First, we assume the absence of surface recombination at the back surface z = t. Second, we allow for an arbitrary surface recombination velocity also at the back surface to obtain a solution for thin films applicable, in particular, to the case of solar cells [26,27].…”

“…The solution of the problem for finite exciton recombination velocities at the planar surface is obtained by considering, instead of the half-space, a finite-thickness slab, whose thickness can be taken sufficiently large. This solution is also generalized for the case of thin films with finite recombination velocity at the back surface, as it is required for solar cells [26,27] solution for a point source of excitons (the Green function) is directly convolved with the numerically calculated distributions of excitons generated by electron beams of different energies. The results of the calculations are applied to describe the contrast of threading dislocations in a freestanding GaN layer with an average distance between dislocations of more than 10 µm.…”