Precise control of nanoscale spacing between electrodes using different natured self-assembled monolayers

• Published in: Nanotechnology 2019-06, Vol.30 (26), p.265302-265302
• Main Authors: You, Young-Jun, Kim, Yongjin, Cheun, Hyeunseok, Shin, Changhwan, Kim, Do Young, Lee, Jae Hak, Song, Joon Yub, Lee, Jae Woo, Lee, Sae Youn, Ju, Byeong-Kwon, Shim, Jae Won
• Format: Article
• Language: English
• Subjects: dip coating; interdigitated horizontal electrode (IHE); nanoscale spacing; self-assembled monolayers (SAMs); surface energy
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/1361-6528/ab0eea

Herein, we introduce an interdigitated horizontal electrode (IHE) structure with a metal-based electron-collecting (or -injecting) electrode and a hole-collecting (or -injecting) electrode composed of a conductive polymeric material that has a nanoscale distance and is horizontally separated. In the IHE, a metal electrode is fabricated on a silicon-oxide substrate, and a self-assembled monolayer (SAM) is selectively bonded to the metal and the oxide to form a conductive polymer electrode by dip coating. Each of the SAM materials is composed of a head part bonded to the substrate surface and a tail part that is hydrophilic or hydrophobic. This inherent property makes the metal electrode hydrophobic and the oxide substrate hydrophilic. Ag is used as a metal electrode material and is combined with alkanethiol SAMs. The alkylsilane SAMs are combined with the silicon oxide substrate to make them hydrophilic, using poly (3, 4-ethylenedioxythiophene)-poly (PEDOT: PSS) as the conductive polymer material. In this study, we have found that there is a difference in the spacing between the two electrodes that depends on the combination of SAM materials. Each interval was spaced from a minimum of 140 nm to a maximum of 385 nm.