1. The University of British Columbia,Department of Materials Engineering,Vancouver,Canada
2. National Taiwan University,Graduate Institute of Electronics Engineering,Taipei,Taiwan
3. National Taiwan University,Graduate Institute of Photonics and Optoelectronics,Taipei,Taiwan
4. National Taiwan University,Graduate School of Advanced Technology,Taipei,Taiwan
5. Fraunhofer Institute for Solar Energy Systems,Heidenhofstrasse, Freiburg,Germany
6. The University of British Columbia,Department of Electrical and Computer Engineering,Vancouver,Canada