Switching of Transfer Characteristics of an Organic Field-Effect Transistor by Phase Transitions: Sensitive Response to Molecular Dynamics and Charge Fluctuation
作者:Seiya Yokokura、Yukihiro Takahashi、Hiroki Nonaka、Hiroyuki Hasegawa、Jun Harada、Tamotsu Inabe、Reiji Kumai、Hiroshi Okamoto、Michio M. Matsushita、Kunio Awaga
DOI:10.1021/acs.chemmater.5b01383
日期:2015.6.23
An organic field-effect transistor was fabricated using an anthracene–tetracyanoquinodimethane (AN–TCNQ) single-crystal charge-transfer (CT) complex as the semiconductor material. The CT complex showed molecular dynamics related to reorientational motion of an AN molecule at room temperature. The transfer characteristics drastically changed when the temperature decreased from room temperature to 90 K: n-type → ambipolar-type → p-type → ambipolar-type. From thermal analysis, AN–TCNQ underwent two phase transitions when the temperature decreased from room temperature to 120 K. To clarify the mechanism of the drastic changes of the transfer characteristics, the crystal and electronic structures of AN–TCNQ at various temperatures were investigated by X-ray structure analysis, optical measurements, and magnetic measurements. It was found that the drastic changes of the transfer characteristics originated from changes in the electronic structure accompanied by the molecular dynamics.
使用蒽–四氰基醌二甲烷(AN–TCNQ)单晶电荷转移(CT)复合物作为半导体材料,制作了有机场效应晶体管。在室温下,该电荷转移复合物表现出与AN分子的重排运动相关的分子动力学。当温度从室温降到90 K时,转移特性发生了剧烈变化:n型 → 双极型 → p型 → 双极型。通过热分析发现,AN–TCNQ在温度从室温降到120 K时经历了两个相变。为了阐明转移特性剧烈变化的机制,采用X射线结构分析、光学测量和磁性测量研究了不同温度下AN–TCNQ的晶体和电子结构。结果发现,转移特性的剧烈变化源于伴随分子动力学的电子结构变化。