High-density polyethylene-an inert additive with stabilizing effects on organic field-effect transistors

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2020-11, Vol.8 (43), p.1546-15415
• Main Authors: Scaccabarozzi, Alberto D, Basham, James I, Yu, Liyang, Westacott, Paul, Zhang, Weimin, Amassian, Aram, McCulloch, Iain, Caironi, Mario, Gundlach, David J, Stingelin, Natalie
• Format: Article
• Language: English
• Subjects: Carrier lifetime; Current carriers; Electron transport; Electronics; Field effect transistors; High density polyethylenes; Mechanical properties; Naphthalene; Optoelectronics; Organic semiconductors; P-type semiconductors; Polyethylene; Polymer blends; Rheological properties; Semiconductor devices; Shelf life; Stability; Thin film transistors; Transistors
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/d0tc03173a

Organic electronics technologies have attracted considerable interest over the last few decades and have become promising alternatives to conventional, inorganic platforms for specific applications. To fully exploit the touted potential of plastic electronics, however, other prerequisites than only electronic functions need to be fulfiled, including good mechanical stability, ease of processing and high device reliability. A possible method to overcome these issues is the employment of insulating:semiconducting polymer blends, which have been demonstrated to display favourable rheological and mechanical properties, generally provided by the insulating component, without negatively affecting the optoelectronic performance of the semiconductor. Here, we demonstrate that binary blends comprising the semicrystalline high-density polyethylene (HDPE) in combination with hole- and electron-transporting organic semiconductors allow fabrication of p-type and n-type thin-film transistors of notably improved device stability and, in some scenarios, improved device performance. We observe, for example, considerably lower subthreshold slopes and drastically reduced bias-stress effects in devices fabricated with a hole-transporting diketopyrrolopyrrole polymer derivative when blended with HDPE and significantly enhanced charge-carrier mobilities and shelf life in case of transistors made with blends between HDPE and the electron-transporting poly{[ N , N ′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)2,6-diyl]- alt -5,5′-(2,2′-bithiophene)}, i.e. P(NDI2OD-T2), also known as N2200, compared to the neat material, highlighting the broad, versatile benefits blending semiconducting species with a semicrystalline commodity polymer can have. The employment of binary blends comprising the insulating polymer HDPE in combination with hole- and electron-transporting organic semiconductors enables fabrication of OTFTs of notably improved device stability and performance.