Enhancing Integrated Circuit Properties through Engineering Backbone Alignment of Conjugated Polymers

In recent years, there has been a growing fascination with polymer materials due to their lightweight and flexible properties. Furthermore, their highly cost-effective manufacturing processes, which employ simple solution methods, have significantly contributed to their surging popularity. Specifically, conjugated polymers of this nature have been widely utilized in various fields like transistors, logic circuits, and sensors, mainly owing to their scalability and affordability. However, it is widely recognized that polymer materials face numerous challenges in terms of their inferior performance compared to inorganic materials.[1] Consequently, extensive research is currently underway to bridge this gap and improve their overall properties. One of the key challenges in manufacturing a logic circuit with polymer is to achieve selectivity in coating a specific conjugated polymer on the target area. Different properties of various conjugated polymer semiconductor materials result in imbalanced operating characteristics of the integrated circuit, and this discrepancy is hard to eliminate. This is an issue that needs to be addressed in CMOS circuits based on conjugated polymers.[2]<br/>This study presents a simple method to align polymer chains in a desired direction, resulting in controlled orientation of polymers, confirmed by UV-Vis spectroscopy and polarized optical microscopy. In contrast, conventional spin-coating techniques show random carbon backbones tangled in various directions. Comparative analysis between transistors fabricated using the proposed method and those made using spin-coating shows higher mobility and on/off ratios in the former. Furthermore, the use of n-type and p-type conjugated polymer semiconductor materials in logic circuitry fabrication achieved superior region selectivity, high mobility, and on/off ratios, leaded to enhanced gain values and noise margins. These findings highlight the potential of conjugated polymer backbone engineering in overcoming semiconductor performance imbalances without changing the geometric structure of components, thus enabling the design of simple symmetric logic circuits. This research provides a promising approch for applying organic semiconductors in various electronic devices.<br/><br/>Keywords: Conjugated polymers, Integrated circuits, Organic electronics, backbone engineering<br/><br/>Acknowledgement<b> : </b>This work was support provided by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2022R1C1C1006036). Also, this research was partially supported by Korea Institute for Advancement of Technology (KIAT) grant funded by the Korea Government (MOTIE) (P0012451, The Competency Development Program for Industry Specialist).<br/><br/>Reference<br/>[1] Yao, Y., Huang, W., Chen, J., Wang, G., Chen, H., Zhuang, X., Ying, Y., Ping, J., Marks, T. J., & Facchetti, A. (2021). Flexible complementary circuits operating at sub-0.5 V via hybrid organic-inorganic electrolyte-gated transistors. <i>Proceedings of the National Academy of Sciences of the United States of America</i>, <i>118</i>(44).<br/>[2] Liao, C., Zhang, M., Yao, M. Y., Hua, T., Li, L., & Yan, F. (2015). Flexible Organic Electronics in Biology: Materials and Devices. In <i>Advanced Materials</i> (Vol. 27, Issue 46).