Basic study on the influence of glass composition and aluminum content on the Ag/Al paste contact formation to boron emitters

Abstract

In this study, the contact formation of aluminum containing silver metallization pastes for boron emitters was investigated. Model pastes with varied glass composition (PbO-containing and PbO-free) and Al content were prepared. It was found, that glass viscosity as well as Al content have a strong influence on densification behavior of the pastes. The most significant effect of the aluminum addition is the change of the thermodynamic conditions in the system silver-glass-silicon. For investigations of the contact formation an in-situ-contact resistance measurement was performed. The interface morphology of the pastes in dependence on the firing temperature was investigated by means of cross section samples in SEM and EDX. Finally, n-type Si solar cells were electrically characterized and the IV-data were correlated to the interface morphology. (C) 2015 The Authors. Published by Elsevier Ltd.