Influence of LPE process technological conditions on Si ELO layers morphology

Epitaxial lateral overgrowth (ELO) is a suitable method which makes it possible to obtain thin layers for applications in the thin film solar cells technology. Due to the method it is possible to save the material which is used in production to make PV modules more economical. Moreover, an ELO layer is partly separated from the growth substrate by an SiO2 cover which prevents propagation of defects into the ELO layer from the substrate. It means that even poor quality silicon substrates can be used to fabricate good quality solar cells. Growing a continuous thin silicon layer on a specially prepared growth silicon substrate is the first step to obtain photovoltaic (PV) modules. The morphology as well as the layer quality and the density of defects depend on various factors: growth temperature, cooling rate, growth time, atmosphere, substrate type, etc. This work presents an analysis of silicon ELO layers growth in different conditions using a horizontal LPE setup. The results can be used to determine the best conditions of growth in order to obtain optimal Si layers for PV applications.