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Title: Textured Poling of the Ferroelectric Dielectric Layer for Improved Organic Field‐Effect Transistors
Abstract

Polymer ferroelectrics are playing an increasingly active role in flexible memory application and wearable electronics. The relaxor ferroelectric dielectric, poly(vinylidene fluoride trifluorethylene (PVDF‐TrFE), although vastly used in organic field‐effect transistors (FETs), has issues with gate leakage current especially when the film thickness is below 500 nm. This work demonstrates a novel method of selective poling the dielectric layer. By using solution‐processed 6,13‐bis(triisopropylsilylethynyl)pentacene (TIPS‐pentacene) as the organic semiconductor, it is shown that textured poling of the PVDF‐TrFE layer dramatically improves FET properties compared to unpoled or uniformly poled ferroelectric films. The texturing is achieved by first vertically poling the PVDF‐TrFE film and then laterally poling the dielectric layer close to the gate electrode. TIPS‐pentacene FETs show on/off ratios of 105and hole mobilities of 1 cm2Vs−1under ambient conditions with operating voltages well below −5 V. The electric field distribution in the dielectric layer is simulated by using finite difference time domain methods.

 
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Award ID(s):
1707588
NSF-PAR ID:
10462165
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Interfaces
Volume:
6
Issue:
4
ISSN:
2196-7350
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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  2. Abstract

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