Polymer field-effect transistors (PFETs) have been extensively studied because of their potential applications in flexible display and wearable electronic devices. Particularly

the design and synthesis of high-performance polymers has become the focus of academic research. A number of studies have shown that the side chains of conjugated polymers not only endow solubility

but also affect the alignment orientation and stacking mode of polymer chains

thus affecting the morphology and properties of semiconductor films. In this mini-review

the recent progress of modification of side chains of conjugated polymers is introduced

including changing the length of side chains

changing the position of side chains

changing the branching position

replacing one bulky branching chain with a linear one

and modifying side chains with functional groups. In addition

the effects of side chain modification on the crystallization process and device performance are highlighted and the future development for in-depth understanding of the side chain effect is discussed.