Developing a numerical model for thin-film transistors has become significant for optoelectronic applications. In this study, we describe the shift of the Dirac point in a graphene oxide thin-film phototransistor doped with various ratios of poly (3-hexylthiophene) (P3HT) (0.01 and 0.05). According the electrical characteristics of graphene oxide/poly (3-hexylthiophene) thin-film transistors and based on the proposed model, we simulate the carrier concentration, the Fermi level (E_f), the mobility (μ), and the conductivity (σ) of charge carriers, the square resistance, and the Seebeck coefficient as a function of the applied gate voltage in the dark and under the illumination of 100 mW/cm², using Matlab/Simulink. The results show that, when applying a negative gate voltage, the Fermi level of graphene will shift below the Dirac point, due to the electrical field effect induced by the P3HT molar ratios and the illumination effect. This shift is exhibited more obviously in the mainly simulated parameters, and can be explained by the molar ratios of P3HT, which modulate the displacement field to allow the opening of a transport band gap through a Colombian force created by the oxygen groups. This work can provide a theoretical basis for analyzing the characteristics of these components for application in the logic circuit domain.

开发薄膜晶体管的数值模型对于光电应用具有重要意义。在这项研究中，我们描述了掺杂有各种比例的聚（3-己基噻吩）（P3HT）（0.01和0.05）的氧化石墨烯薄膜光电晶体管中Dirac点的位移。根据氧化石墨烯/聚（3-己基噻吩）薄膜晶体管的电学特性，并基于所提出的模型，我们模拟了载流子浓度，费米能级（E _f），迁移率（μ）和电导率（σ）载流子的电荷），方电阻和塞贝克系数与在黑暗中以及在100 mW / cm ²的光照下施加的栅极电压的函数，使用Matlab / Simulink。结果表明，当施加负栅极电压时，由于P3HT摩尔比引起的电场效应和照明效应，石墨烯的费米能级将移动到Dirac点以下。这种位移在主要模拟的参数中更明显地显示出来，并且可以通过P3HT的摩尔比来解释，P3HT的摩尔比调节位移场，以允许通过由氧基团产生的哥伦比亚力打开传输带隙。这项工作可以为分析用于逻辑电路领域的这些组件的特性提供理论依据。