Characterization of the Organic Thin Film Solar Cells with Active Layers of PTB7/PC₇₁BM Prepared by Using Solvent Mixtures with Different Additives

Table 4

Surface roughness parameters of the PTB7:PC₇₁BM active layer obtained from AFM analysis.

Layer	Peak-to-valley; [nm]	Root-mean-square roughness; [nm]
PTB7:PC71BM with pristine CB	13.4	1.18
PTB7:PC71BM with CB and DIO (3 v%)	10.7	0.53
PTB7:PC71BM with CB and CN (3 v%)	11.8	0.72
PTB7:PC71BM with CB and DIO (3 v%)+CN (3 v%)	7.4	0.64