Variation of the Side Chain Branch Position Leads to Vastly Improved Molecular Weight and OPV Performance in 4,8-dialkoxybenzo[1,2-b:4,5-b′]dithiophene/2,1,3-benzothiadiazole Copolymers

Figure 5

Electrical characteristics of P1 (black), P2 (blue), and P3 (red). Each device has dimensions 𝐿=5 μm and 𝑊=1000 μm. A plot of the log(𝐼_D) versus 𝑉_GS in open symbols (right axis) and the 𝐼^1/2_D versus 𝑉_GS in solid symbols (left axis) in the saturation regime (𝑉_DS=−60 V) are shown.