新型聚合物半导体薄膜及其场效应晶体管的研究

doi:10.3969/j.issn.1000-5641.201922006

摘要/Abstract

摘要： 以新型的有机聚合物半导体（DPPTTT （poly （3，6-di （2-thien-5-yl）-2，5-di （2-octyldodecyl）-pyrrolo[3，4-c]pyrrole-1，4-dione） thieno[3，2-b]thiophene））为研究对象，利用溶液法制备了有机半导体薄膜并进行了一系列表征.发现半导体薄膜的厚度、表面粗糙度和拉曼峰强度均随溶液浓度和转速呈规律性变化.以该材料作为半导体活性层制备了p型有机场效应晶体管，发现当沟道长度降低到50 μm时，器件的有效载流子迁移率最高，达到0.12 cm²/Vs；同时观察到随着沟道长度的降低，载流子迁移率与阈值电压都有增大的趋势，这与普遍观察到的短沟道效应相反.这些研究内容或许可以为更好地理解有机场效应晶体管及器件物理提供新的观点.

关键词: 有机场效应晶体管, 聚合物半导体, 溶液法, 短沟道效应, 接触电阻

Abstract: Thin films using a novel organic polymer semiconductor (DPPTTT(poly(3,6-di(2-thien-5-yl)-2,5-di(2-octyldodecyl)-pyrrolo[3,4-c]pyrrole-1,4-dione) thieno [3,2-b] thiophene)) were prepared by a solution process and characterized through different techniques. It was found that the thickness, surface roughness, and Raman peak strength of the semiconductor films changed with the solution concentration and rotation rate. The polymer semiconductor was used to prepare the active layer for p-type organic field effect transistors; with these, the influence of channel length on critical transistor parameters (i.e., carrier mobility and threshold voltage) was studied. It was found that the effective carrier mobility was the highest at 0.12 cm²/Vs when the channel length was reduced to 50 μm. With a decrease in channel length, both carrier mobility and threshold voltage tended to increase, which was contrary to the short channel effect. This paper may provide new perspectives for better understanding the physics of field effect transistor devices.

Key words: organic field effect transistor, polymer semiconductor, solution process, short channel effect, contact resistance

中图分类号:

O472+.4

叶建春, 周礼照, 李文武, 欧阳威. 新型聚合物半导体薄膜及其场效应晶体管的研究[J]. 华东师范大学学报（自然科学版）, 2020, 2020(1): 83-92.

YE Jianchun, ZHOU Lizhao, LI Wenwu, OU-YANG Wei. Novel polymer semiconductor films and related field effect transistor devices[J]. Journal of East China Normal University(Natural Science), 2020, 2020(1): 83-92.

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