**Effects of Optical Interference and Annealing on the Performance of Polymer/Fullerene Bulk Heterojunction Solar Cells**

Chunfu Zhang1, Hailong You1, Yue Hao1, Zhenhua Lin2 and Chunxiang Zhu2 *1School Of Microelectronics, Xidian University, 2ECE, National University of Singapore, 1China 2Singapore* 
