Kim Do-Kyung, Lee Hyeonju, Zhang Xue, Bae Jin-Hyuk, Park Jaehoon
School of Electronics Engineering, Kyungpook National University, Daegu 41566, Korea.
Department of Electronic Engineering, Hallym University, Chuncheon 24252, Korea.
Micromachines (Basel). 2019 Oct 28;10(11):727. doi: 10.3390/mi10110727.
Flexible organic ferroelectric field-effect transistors (Fe-FETs) have attracted attention for next-generation memory applications. A fundamental understanding of the electrical properties and mechanical stability of transistors is a prerequisite to realizing practical flexible electronics. Here, we demonstrate the solvent-dependent electrical characteristics and mechanical stability of flexible Fe-FETs. Poly(vinylidene fluoride-trifluoro-ethylene) (P(VDF-TrFE)) based Fe-FETs were fabricated by using dimethylformamide (DMF) and methyl ethyl ketone (MEK) solvents on a polyimide substrate. P(VDF-TrFE) from DMF formed a smoother surface than a surface from MEK; the surface property greatly affected the electrical properties and mechanical stability of the devices. Larger hysteresis and higher mobility were obtained from Fe-FET using DMF compared to those characteristics from using MEK. Furthermore, Fe-FET using DMF showed lower degradation of on-current and mobility under repetitive mechanical stress than an MEK-based Fe-FET, due to its excellent semiconductor-insulator interface. These results will guide appropriate solvent selection and contribute to the improvement of flexible Fe-FET electrical properties and mechanical stability in the next generation of memory devices.
柔性有机铁电场效应晶体管（Fe-FET）在下一代存储器应用中受到了关注。对晶体管的电学性能和机械稳定性有基本的了解是实现实用柔性电子器件的前提条件。在此，我们展示了柔性Fe-FET的溶剂依赖性电学特性和机械稳定性。基于聚偏二氟乙烯-三氟乙烯（P(VDF-TrFE)）的Fe-FET是通过在聚酰亚胺基板上使用二甲基甲酰胺（DMF）和甲乙酮（MEK）溶剂制备的。来自DMF的P(VDF-TrFE)形成的表面比来自MEK的表面更光滑；表面性质极大地影响了器件的电学性能和机械稳定性。与使用MEK的情况相比，使用DMF的Fe-FET具有更大的滞后和更高的迁移率。此外，由于其优异的半导体-绝缘体界面，使用DMF的Fe-FET在重复机械应力下的导通电流和迁移率的退化比基于MEK的Fe-FET更低。这些结果将指导合适的溶剂选择，并有助于改善下一代存储器件中柔性Fe-FET的电学性能和机械稳定性。
