Tetiana Olar

ERS 3.1 Tetiana Olar – PhD student at Helmholtz-Zentrum Berlin

A joint Master in Nanoscience was received at University of Basque Country, Spain and at Taras Shevchenko National University of Kyiv, Ukraine. The multidisciplinary training was given in physics, chemistry, engineering and complementary subjects. The thesis was focused on glass transition phenomena in polystyrene thin films tackled by fast calorimetry.

The individual research project “Implementation of solar cells” of WP3 has the goal to examine junction formations on CTZS absorbers for CZTS based heterojunctions. Secondly, the development of adapted buffer layers and transparent conductive oxides are objectives, including the investigation of surface and interface properties and assessment of current transport. In order to reach the mentioned aims systematic combinations of absorbers with different buffer materials will be investigated on the basis of theoretical considerations. Photoelectron spectroscopy is the main tool to determine the band-line-up and to characterize interfaces of each combination of window-buffer-absorber-back contact layers. Taking into account the obtained results, the systematic surface and interface modification will be performed to improve the band-line-up. And of course, analysis of CTZS(Se)/buffer interface properties should be taken into account.

Papers:

T. Olar, I. Lauermann, H. Xie, M. NEUSCHITZER, E. Saucedo, W. Calvet, A.r Steigert, B. Ümsür, B. Chacko, V. Parvan, M. Gorgoi, B. Senkovskiy, M.Ch Lux-Steiner. “Assessment of Chemical and Electronic Surface Properties of the Cu 2 ZnSn (SSe) 4 After Different Etching Procedures by Synchrotron-based Spectroscopies”, Energy Procedia, Vol.84, 080-016, (2015). DOI:10.1016/j.egypro.2015.12.289

M.NEUSCHITZER, Y. Sánchez, T. OLAR, T Thersleff, S López-Marino, F Oliva, M Espindola-Rodriguez, H. Xie, Ml Placidi, V Izquierdo-Roca, I Lauermann, K Leifer, A. Perez-Rodriguez, E Saucedo “The complex surface chemistry of kesterites: Cu/Zn re-ordering after low temperature post deposition annealing and its role in high performance devices”. “Chemistry of Materials” (2015) 27(15) pp5279-5287. 10.1021/acs.chemmater.5b01473

H. Xie, S. López-Marino, T. Olar, Y. Sánchez González, M. NEUSCHITZER, Florian Oliva, S. Giraldo, V. Izquierdo-Roca, I. Lauermann, A. Pérez-Rodríguez, E. Saucedo “On the Impact of Na Dynamics at the Cu2ZnSn (S, Se) 4/CdS Interface During Post Low Temperature Treatment of Absorbers”, ACS applied materials & interfaces, (2016). DOI:10.1021/acsami.5b12243

Conferences:

T. Olar,  I. Lauermann,  H.Xie, E.Saucedo, W. Calvet, A. Steigert, B. Ümsür,  Martha Ch. Lux-Steiner. “Diffusion of indium in kesterite thin-film solar cells investigated by hard x-ray photoelectron spectroscopy”. The 562nd Wilhelm and Else Heraeus-Seminar “From Sunlight to Fuels”.May 2014, Bad-Honnef, Germany.(Poster)

T. Olar,  I. Lauermann,  H.Xie, E.Saucedo, W. Calvet, A. Steigert, B. Ümsür, B. Chacko ; V. Parvan,  Martha Ch. Lux-Steiner.“Assessment of the Cu2ZnSnSSe4 chemical and electronic surface properties after different etching procedures by synchrotron-based spectroscopies”. E-MRS Spring meeting Lille, France 2015.(Oral)

I. Lauermann and T. Olar. Diffusion of indium in kesterite thin-film solar cells investigated by hard x-ray photoelectron spectroscopyIn: Annual meeting of Institut Materiaux Microelectronique Nanosciences de Provence, Casis ,France, 2014(Poster)

I. Lauermann and T. Olar. Diffusion of indium in kesterite thin-film solar cells investigated by hard x-ray photoelectron spectroscopyIn: French Kestrite Meeting, Grenoble, France, 2014(Poster)

T. Olar and I. Lauermann Diffusion of indium in kesterite thin-film solar cells investigated by hard x-ray photoelectron spectroscopy. In: 562nd Wilhelm and Else Heraeus-Seminar “From Sunlight to Fuels”. Bad-Honnef, Germany, 2014. (Poster).