Observation of interface trap reduction in fluoropolymer dielectric organic transistors by low-frequency noise spectroscopy

This study examines the low-frequency noise characteristics of the 2,7-dioctyl[1] benzothieno[3,2-b][1] benzothiophene organic thin-film transistor (OTFT) having a CYTOP dielectric layer. Specifically, the fabricated OTFT exhibits 1/f noise, and its behavior is explained via a carrier number fluctuation model. Additionally, the volume trap density (NT) of the gate dielectric is quantitatively evaluated and compared with its counterpart having SiO2 dielectric layer. The analysis of the results shows that the hydrophilic entities of the dielectric layer strongly influence the NT, while the CYTOP having hydrophobic properties provides less NT than that of SiO2.