Invited talk at the Princeton University, 11 Aug 2015.
B.05 Guest lecturer at an institute/university
COBISS.SI-ID: 11095636In solar cells the transparent conductive oxides (TCO) are important for collection of free carriers and minimization of the optical losses in the broad wavelength region (400–1200 nm). The research for the solar cells has been mostly focused on In2O3-SnO2 (ITO) films. In this work we studied Ga doped ITO (GITO) film, the material which in contrast to standard ITO 90/10 contains less In, but exhibits better mobility and lower parasitic absorption at low (200 ºC) deposition and annealing temperatures. A multicomponent Ga-In-Sn oxide target was fabricated and used in the RF sputtering system for deposition of GITO thin films on glass substrates. Finally the microstructural/structural (SEM, XRD, XPS), optical and electrical properties of the thin films deposited at optimal sputtering conditions were measured. At low deposition and annealing temperatures we obtained optically better GITO thin film compared to ITO 90/10 one. Additionally, the measurements show 20% lower resistivity of GITO films than ITO 90/10.
B.03 Paper at an international scientific conference
COBISS.SI-ID: 11258196Invited talk
B.04 Guest lecture
COBISS.SI-ID: 11349844At the Symposium Y - “Advanced materials and characterization techniques for solar cells II” (European Materials Research Society Spring Meeting 2014, Lille, 24-30 May 2014) the invited talk "Approaches and challenges in optical modeling and characterization of thin-film solar cells" reviewed state-of-the-art modeling approaches and highlighted challenges in R&D of thin-film solar cells. Performance of thin film solar cells needs accelerated improvements. Where is the unused potential? Apart from inevitable energy conversion losses, both electrical and optical losses need to be defragmented per thin-film cell structure to path a way to further improvements. In case of TF-Si photon management is crucial for further improvement of conversion efficiency. By means of optical modeling losses are simulated and potential improvements in quality of materials discussed. Optical simulators developed at University of Ljubljana SunShine, FEMOS and CROWM are briefly reviewed and combined with rigorous 3D simulations based on COMSOL software. Finally, the record thin film solar cell are compared to the record crystalline solar cells and unused potential in performance of thin film solar cells is pointed out.
B.04 Guest lecture
An overview of selected nanostructures introduced in c-Si solar cells is given. Activities of our lab in this field are presented, in particular: results on UV nanoimprint lithography for replication of nanostructures to large areas, optical characterization of nanostructures and optical modelling of solar cells including nanostructures. A camera based angular resolved spectroscopy system is presented. Coupled modelling approach is used to meet the challenges of modelling of c-Si solar cells with nano and macro structures for efficient light confinement.
B.04 Guest lecture
COBISS.SI-ID: 11216468