Effect of Gaussian Disorder on Power-Law Contact Resistance and Mobility in Organic Field-Effect Transistors

We study the effect of Gaussian energetic disorder on the organic field-effect transistors (OFETs) with surprisingly high field-effect mobility and the low contact resistance. The numerical device simulation assumes the thermally assisted hopping transport and injection in disordered semiconductors. The results are analyzed with the power-law field-effect mobility and the asymptotic power-law contact resistance model. Transistor parameters extracted by the models reveal that a higher Gaussian disorder, which leads to a lower injection barrier and a larger mobility enhancement, is the origin of the high field-effect mobility and the low contact resistance.