Regensburg 2013 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

HL: Fachverband Halbleiterphysik

HL 87: Goup IV elements and their compounds II

HL 87.2: Talk

Thursday, March 14, 2013, 16:00–16:15, H15

Defect states at c-Si/a-Si₃N_xH_y interfaces — •Leif Eric Hintzsche¹, Gerald Jordan¹, Martijn Marsman¹, Machteld Lamers², Arthur Weeber², and Georg Kresse¹ — ¹University of Vienna, Faculty of Physics and Center for Computational Materials Science, Sensengasse 8/12, A-1090 Vienna, Austria — ²ECN Solar Energy, P.O. Box 1, 1755 ZG Petten, Netherlands

Amorphous silicon nitrides are deposited on crystalline silicon as antireflection and passivating coatings. Up to date detailed knowledge about the interfaces is largely lacking. We have investigated the electronic and structural properties of c-Si/a-Si₃N_xH_y interfaces obtained by large scale ab initio molecular dynamics simulations. Over 500 independent samples have been generated for each considered stoichiometry to perform a reliable defect analysis. While the classes of dominant defect states coincided with previous bulk calculations, we found a considerably increased defect density at the interface. By applying an energy and spatially resolved defect analysis, we observed that most of the defect states originate from the first silicon nitride layer at the interface. Additionally, we examined passivation effects of hydrogen at the interface which play an important role to increase the efficiency of modern solar cells.