1. Institute of Technical Physics and Materials Science, HAS Centre for Energy Research, P.O.
Box 49, H-1525 Budapest, Hungary
2. Institute of Microelectronics and Technology, Óbuda University, Tavaszmező u. 17, H-1084 Budapest, Hungary
3. Winger Research Centre for Physics, Institute for Particle and Nuclear Physics, Konkoly-Thege M. str. 29-33, H-1121 Budapest, Hungary