Ryu Jehyeok, Jo Jeong-Sik, Choi Jin-Hyun, Kim Deuk Young, Kim Jiyoun, Park Dong Hyuk, Jang Jae-Won
Department of Physics, Pukyong National University, Busan 48513, Republic of Korea.
Division of Physics and Semiconductor Science, Dongguk University, Seoul 04620, Republic of Korea.
ACS Omega. 2023 Mar 8;8(11):10439-10448. doi: 10.1021/acsomega.3c00038. eCollection 2023 Mar 21.
Using scanning probe lithography (SPL) with KOH ink, this study fabricates aluminum hydroxide (Al(OH)) nano- and microfeatures on a gold (Au) film that has been deposited on an aluminum (Al) layer. Hydroxyl ions (OH) from the KOH ink loaded onto the Au film can react with the underlying Al layer to form Al(OH) structures due to the decrease in the pH of the reacting solution. In this process, Al(OH) solidification is governed by the pH of the KOH ink solution, which is affected by its volume. Suitably small volumes (down to hundreds of attoliters) of the KOH ink solution can be applied to the substrate surface using dip-pen nanolithography (DPN) and polymer-pen lithography (PPL). Using DPN and PPL printing with the solid (i.e., gel) and liquid phases of KOH ink, sub-micron- (minimum ≈300 nm) and micron-sized (≥4 μm) Al(OH) features can be obtained, respectively. The fabrication of Al(OH) structures using the proposed pH-dependent solidification process can be achieved with relatively small volumes in ambient conditions without requiring a previously reported molding process..
本研究使用带有氢氧化钾（KOH）墨水的扫描探针光刻技术（SPL），在沉积于铝（Al）层上的金（Au）膜上制备氢氧化铝（Al(OH)）纳米和微米级特征结构。加载到金膜上的KOH墨水中的氢氧根离子（OH），由于反应溶液pH值的降低，可与下层的Al层反应形成Al(OH)结构。在此过程中，Al(OH)的固化受KOH墨水溶液pH值的控制，而pH值又受其体积的影响。使用浸笔纳米光刻技术（DPN）和聚合物笔光刻技术（PPL），可以将适当小体积（低至数百阿托升）的KOH墨水溶液施加到基底表面。分别使用KOH墨水的固相（即凝胶）和液相进行DPN和PPL打印，可以获得亚微米级（最小约300 nm）和微米级（≥4μm）的Al(OH)特征结构。利用所提出的pH值依赖性固化过程制备Al(OH)结构，在环境条件下使用相对较小的体积即可实现，无需先前报道的成型工艺。
