Stephan van Duren

ESR 4.2 Stephan van Duren PhD student at Helmholtz-Zentrum Berlin

At Utrecht University he received a bachelor degree in Physics. He gained interest in renewable energies and decided to obtain a Master in Energy Science. During this education he gained knowledge about the physical and chemical background of a wide range of renewable energies. His main interest became photovoltaics. In this field, he performed his master research and studied plasmonic effects in metal nanostructered solar cells.

Currently, he participates in the Kestcells project and his main topic of his PhD is focused on development of optical techniques for in-situ process control and monitoring. He analysed and worked with different (vacuum) techniques for absorber fabrication. Analysis included the impact of process parameters, such as temperature, on compositional and morphological absorber homogeneity. Reflectometry as a tool for in-situ phase identification/evolution was studied. For this purpose an optical setup was designed and built. Secondary phases and absorbers with different composition were studied in- and ex-situ at different temperatures. This was supplemented with compositional, structural and morphological analysis and simulations of reflection spectra. Further in-situ studies of different secondary phases and CZTS absorbers are currently investigated with Raman spectroscopy.

Papers:

S. VAN DUREN, Y. REN, J.Scragg, J.Just, T.Unold. Raman spectroscopy study on in-situ monitoring of Cu2ZnSnS4 synthesis. IEEE 2015 conference proceedings.

Conferences:

Stephan van Duren, Yi Ren, Jonathan Scragg, Justus Just, Thomas Unold “Raman spectroscopy study on in-situ monitoring of Cu2ZnSnS4 synthesis” In: 42nd IEEE Photovoltaic Specialist Conference, New Orleans, 2015 (oral)

Justus Just, Steffen Kretzschmar, Stephan van Duren, Roland Mainz, Claudia Coughlan and Thomas Unold “High Vapour Pressure Selenization and Grain Growth Mechanisms of Sulfide-CZTS Precursors” In: 4th European Kesterite Workshop. Berlin, Germany, 2013. (oral).

High Vapour Pressure Selenization and Grain Growth Mechanisms of Sulfide-CZTS Precursors. 4th European kesterite meeting, Berlin

Stephan van Duren, Sergei Levcenco, Justus Just and Thomas Unold “Reflectometry as a non-destructive tool for CZTS-synthesis control” In: DPG Conference Spring Meeting, Berlin 2015 (poster)

Stephan van Duren, Sergei Levcenco, Justus Just and Thomas Unold “Reflectometry as a non-destructive tool for CZTS-synthesis control” In: 5th European Kesterite Workshop in Tallinn, Estonia, 2014 (poster)

S. van Duren, Y. Ren, J. Scragg, J. Just, T. Unold, “Temperature dependent Raman scattering of CuS, ZnS, SnxSy, CuxSnSy and Cu2ZnSnS4 for in-situ process control”, Presented at EU PVSEC. Hamburg, Germany. 2015. (Poster).