Effects of Annealing Conditions on ZnO Buffer Layer for Inverted Polymer Solar Cells

Chuan Liu, Lihua Zheng, Zhiyang Gao, Yuhui Gan, Jian Zhang, Chuannan Li

State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Qianjin Street, Changchun, China.

DOI: 10.4236/opj.2013.32B052                

Abstract

A solution-processed zinc oxide (ZnO) thin film as the buffer layer with optimized processes especially the annealing conditions for inverted polymer solar cells (PSCs) has been demonstrated. Firstly the thickness of ZnO buffer layer was optimized, and different annealing conditions including temperature and time have also been taken into consideration. And the best Power Conversion Efficiency (PCE) 3.434% was observed when the ZnO buffer layer was spin–coated at 1500 rpm and annealed at 275℃ for 5 min, and AFM results showed that morphology of this ZnO film has the best uniformity which was beneficial to form high quality polymer composite active layer.

Keywords

Polymer Solar Cells (PSCs); Zinc Oxide; Buffer Layer; Annealing; Morphology

Conflicts of Interest

The authors declare no conflicts of interest.

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