1. Institute of Physics of the ASCR,Dept. of Thin Films and Nanostructures,Prague,Czech Republic
2. Institute of Physics of the ASCR,Dept. of Semiconductors,Prague,Czech Republic
3. Institute of Physics of the ASCR,Dept. of Optical Materials,Prague,Czech Republic
4. Univ. of Techn. and Education,Dept. of Renewable Energy,Ho Chi Minh City,Vietnam
5. Center of Physics, Inst. of Appl. Mech. and Informatics,Ho Chi Minh City,Vietnam