The impact of thermal annealing temperature on the low-frequency noise characteristics of P3HT:PCBM bulk heterojunction organic solar cells

• Published in: Solar energy materials and solar cells 2014-11, Vol.130 (C), p.151-155
• Main Authors: Li, Lijun, Shen, Yang, Campbell, Joe C.
• Format: Article
• Language: English
• Subjects: Annealing; Applied sciences; Bias; Bulk heterojunction; Density; Diagnostic systems; Electrical engineering. Electrical power engineering; Electrical power engineering; Energy; Exact sciences and technology; Heterojunctions; Low-frequency noise; Material characterization; Natural energy; Noise; Operation. Load control. Reliability; Organic solar cells; Photovoltaic cells; Photovoltaic conversion; Power networks and lines; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2014.07.009

We investigate the dark low-frequency noise characteristics of P3HT:PCBM bulk heterojunction organic solar cells in both forward and reverse bias conditions. The current noise power spectral density (SI) is “1/f”-like and is compared among cells annealed at different temperatures (60°C to 140°C). The asymmetric relationship of SI versus DC dark current (IDC) can be explained by the competition between the recombination current noise and tunneling current noise. Among the different annealing temperatures, we find that higher annealing temperature yields smaller ratio of the Hooge parameter to the carrier recombination lifetime, which is reflected in the forward bias SI versus IDC relationship. We demonstrate that the low-frequency noise can serve as a non-destructive diagnostic indicator of the performance of organic solar cells. •We measure the low-frequency noise of organic solar cells annealed at 60°C–140°C.•We examine the current noise power in both forward and reverse bias.•We attribute the noise behavior to the competition between two noise mechanisms.•We find the low-frequency noise is a diagnostic indicator of the material quality.