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

Table 2

Surface roughness parameters of the PTB7 thin films obtained from AFM analysis.

Layer	Peak-to-valley; [nm]	Root-mean-square roughness [nm]
PTB7 with pristine CB	7.0	0.7
PTB7 with CB and DIO (3 v%)	12.7	1.5
PTB7 with CB and CN (3 v%)	9.3	0.6