A method of forming a polymer, the method comprising combining 4-bromo-7-[5-bromo-4-(alkyl)thiophen-2-yl]-6-chloro-5-fluoro-2,1,3-benzothiadiazole, (3,3′-difluoro-[2,2′-bithiophene]-5,5′-diyl)bis(trimethylstannane), [4-(alkyl)-5-[5-(trimethylstannyl)thiophen-2-yl]thiophen-2-yl]trimethylstannane, tris(dibenzylideneacetone), and dipalladium P(o-tol)3 tris(2-methylphenyl)phosphane to form the polymer: In this polymer, W is selected from the group consisting of: S, Se, O, and N-Q. Additionally, Q is selected from the group consisting of: a straight-chain carbyl, silyl or hydrocarbyl, branched, cyclic alkyl with 1 to 30 atoms, and fused aromatic rings. Furthermore in this polymer, R1, and R4 are independently selected from the group consisting of: F, Cl, I, Br, CN, —NCO, —NCS, —OCN, —SCN, —OX, —SX, —NH2, —C(═O)X, —C(═O)—OX, —OX, —NHX, —NXX′, —C(═O)NHX, —C(═O)NXX′, —SO3X, —SO2X, —OH, —NO2, CF3, —SF5, a straight-chain or branched carbyl, silyl, or hydrocarbyl, a branched or cyclic alkyl with 1 to 30 atoms, a fused substituted aromatic ring, and a fused unsubstituted aromatic ring. This polymer can also have R2 and R3 are independently selected from F, Cl, Br and I. Additionally, in this polymer, the fused aromatic rings can be independently fused with groups consisting of: a straight-chain or branched carbyl, silyl, or hydrocarbyl, a branched or cyclic alkyl with 1 to 30 atoms, a fused substituted aromatic ring, and a fused unsubstituted aromatic ring. Lastly, in this polymer, h+j is between 0.2 to 0.6 and i+k is between 0.4 and 0.8.