Novelty Approach to GaAs Solar Cells Modelling

In this article the classical approach to GaAs based solar cells modeling has been improved by taking into account additional physical mechanisms like surface recombination, radiation recombination, and non-radiation recombination, which have a significant impact on to modeling result but were not previously considered in the early developed physical model. Among these types the surface recombination is the most valuable because it connected with surface states that introduce the energy level that lies in the semiconductor bandgap between the valence and conduction bands. The quality of semiconductor material directly affected on surface states concentration which connected with crystal boundary action and impurity's adsorption on the end surface. In improved model also have been included the photon recycling mechanism which plays an important role in approaching GaAs based solar cells model to the full compliance. Building a photon re-absorption model and assuming some boundary conditions has been carried out using the modifying Steiner model and in addition with detailed consideration of recombination processes on the device inner surfaces were allow to modeling not only single-junction GaAs solar cells but also multi-junction elements with maximum conversion efficiency. It has been shown that main components to increase GaAs based solar cells efficiency are low surface recombination velocity and realization of good rear-side mirror.