LiPON (lithium-phosphorous-oxynitride), a solid state electrolyte for all-solid state Li ion batteries, was characterised in detail by XPS core level analysis. Different compositional structures were found for depositions at different sample temperatures. As known, the replacement of bridging oxygen by nitrogen plays an important role and the nitrogen XPS signal can be divided into two emission lines at different binding energies. These details have already been analysed in dependence on the deposition power and nitrogen pressure during deposition. In this contribution we have investigated the LiPON deposition at different temperatures by XPS and impedance measurements. Different conductivity values could be linked to structural differences that were investigated by XPS core level analysis. Additionally, the activation energies were compared for the electrolytes obtained for depositions at different substrate temperatures. (C) 2010 Elsevier B.V. All rights reserved.