To evaluate the electrical performance of OFETs based on these indoloindolizine derivatives, we recorded current-voltage (I-V) characteristics and transfer curves at various gate voltages (Figure ,b, Section S7). The output characteristics (Figure ) demonstrate the ambipolar behavior of all measured compounds, with the drain current modulated by the gate voltage. At low drain voltages, the non-linear shape of the curves indicates contact resistance and suggests the presence of charge trap states in the materials. Additionally, the transfer characteristics for both negative and positive drain voltages (Figures ) have symmetric shapes, indicating balanced electron and hole populations within the devices. The threshold voltages for p-type operation are approximately -30 V and are similar across all compounds, whereas for n-type operation, the threshold voltages range from 10 to 15 V, depending on the specific compound. These relatively high threshold voltages for both n-and p-channel operations may indicate charge injection limitations and strong charge carrier trapping at the semiconductor-dielectric interface, with hole trapping being more pronounced. Notably, the transfer characteristics of I8a reveal weaker electron trapping than the other derivatives (Figure ). However, further optimization of the silyl side groups and deposition processes is needed to reduce charge trapping, which will be the focus of future studies.