A Sub‐20 nm Organic/Inorganic Hybrid Dielectric for Ultralow‐Power Organic Thin‐Film Transistor (OTFT) With Enhanced Operational Stability. Issue 39 (26th August 2022)

• Record Type: Journal Article
• Authors: Choi, Junhwan; Lee, Chungryeol; Kang, Juyeon; Lee, Changhyeon; Lee, Seung Min; Oh, Jungyeop; Choi, Sung‐Yool; Im, Sung Gap
• Is Part Of: Small. Volume 18:Issue 39(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-26
• Subjects: high‐k polymer dielectrics -- low‐voltage operation -- operational stability -- organic thin‐film transistors (OTFTs) -- organic/inorganic hybrid dielectrics; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202203165
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: Organic/inorganic hybrid materials are utilized extensively as gate dielectric layers in organic thin‐film transistors (OTFTs). However, inherently low dielectric constant of organic materials and lack of a reliable deposition process for organic layers hamper the broad application of hybrid dielectric materials. Here, a universal strategy to synthesize high‐ k hybrid dielectric materials by incorporating a high‐ k polymer layer on top of various inorganic layers generated by different fabrication methods, including AlO x and HfO x, is presented. Those hybrid dielectrics commonly exhibit high capacitance (>300 nF·cm –2 ) as well as excellent insulating properties. A vapor‐phase deposition method is employed for precise control of the polymer film thickness. The ultralow‐voltage (<3 V) OTFTs are demonstrated based on the hybrid dielectric layer with 100% yield and uniform electrical characteristics. Moreover, the exceptionally high stability of OTFTs for long‐term operation (current change less than 5% even under 30 h of voltage stress at 2.0 MV·cm –1 ) is achieved. The hybrid dielectric is fully compatible with various substrates, which allows for the demonstration of intrinsically flexible OTFTs on the plastic substrate. It is believed that this approach for fabricating hybrid dielectrics by introducing the high‐ k organic material can be a promising strategy for future low‐power, flexible electronics. Abstract : Organic/inorganic hybrid dielectric layers are developed based on high‐ k polymer and inorganic oxide layers. The ultralow‐voltage (<3 V) organic thin‐film transistor (OTFT) is demonstrated with exceptionally high stability in long‐term operation. A vapor‐phase deposition method for the polymer layer enables the nanoscale thickness control, thus allowing for the systematic optimization of the device performance as well as high uniformity.