https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/233 Fri, 24 Jul 2026 06:06:45 GMT 2026-07-24T06:06:45Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/212266 Title: Substrate-field-modulated remote-van der Waals hybrid epitaxy in transition metal dichalcogenide heterostructures Authors: Handriani, Lia Saptini; Jang, Suhee; Kim, Yelim; Yun, Hyuncheol; Jeong, Dae Yeop; Park, Hyeonsu; Gao, Zhe; Jang, Jae-il; Park, Won Il Abstract: Two-dimensional (2D) transition-metal dichalcogenide (TMDC) heterostructures are promising for next-generation optoelectronics, yet the mechanisms controlling their vertical heteroepitaxy remain poorly understood. Here, we systematically investigate metal–organic chemical vapor deposition growth of MoS2/WS2 and WS2/MoS2 vertical heterostructures across varying interlayer thicknesses (monolayer to multilayer) and substrates (Si, SiO2 and c-sapphire). We identify a substrate-field-modulated “remote–van der Waals (vdW) hybrid epitaxy” regime, in which vertical overgrowth is confined to a narrow thickness window (~ 1–3 layers), with nucleation density strongly influenced by substrate polarity and defect chemistry. High-resolution STEM reveals that, in the regions where vertical growth occurs, the in-plane crystallographic registry is primarily governed by vdW coupling to the 2D template, yielding a highly preferred single-orientation registry across the examined regions for both stacking orders. This dual-control mechanism decouples growth propensity from epitaxial alignment, providing a scalable framework for synthesizing high-quality 2D vertical heterostructures with precisely engineered interfaces. Tue, 01 Dec 2026 00:00:00 GMT https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/212266 2026-12-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/218683 Title: Capacitance enhancement of Ru/ZrO2/Ru metal–insulator–metal capacitors via the annealing-induced densification of the top Ru electrode Authors: Park, Jun Hyeong; Kim, Sung Jun; Jung, Hoi Yoon; Shin, Wangchul; Lee, Taeho; Park, In-Sung; Park, Young Wook; Ahn, Jinho Abstract: Ru films deposited via atomic layer deposition (ALD) typically exhibit island-like growth on oxide substrates, which degrades their mechanical and electrical properties. The reduction of structural defects in Ru films (including voids within the film bulk and loose bonds at the electrode/dielectric interface) by electrode annealing can increase the capacitance of Ru/ZrO2/Ru capacitors. However, the post-deposition annealing (PDA) of Ru electrodes in such capacitors has not been examined in detail. The capacitance enhancement of Ru/ZrO2/Ru capacitors was investigated by annealing their top Ru electrodes, which led to film densification. Structural and electrical analyses involving X-ray reflectivity, transmission electron microscopy, and adhesion tests revealed that annealing-induced densification of the Ru film lowered the film resistivity and strengthened interfacial adhesion. Consequently, PDA of the ALD-Ru top electrode resulted in an 11–16% increase in the capacitance of Ru/ZrO2/Ru capacitors compared to those with an as-deposited Ru top electrode. Sun, 01 Nov 2026 00:00:00 GMT https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/218683 2026-11-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/218613 Title: Plasma dry desmear of Ajinomoto build-up film for fine micro-via fabrication in advanced semiconductor packaging Authors: Kim, Gyulee; Kim, Sunbum; Min, Kyoung Yeon; Han, Young Ju; Jeong, Soonoh; Kim, Mooseong; Choi, Changhwan Abstract: The increasing demand for high-performance computing and AI applications has accelerated the development of advanced semiconductor packaging technologies with high I/O density. Ajinomoto build-up film (ABF) is widely used as a dielectric material in redistribution layers (RDLs) due to its low dielectric constant and low thermal expansion coefficient. However, laser drilling of ABF generates residual smear composed of silica and polymeric resin, which deteriorates copper adhesion and signal reliability in micro-via structures. In this study, a plasma-based dry desmear process using CF4/O2/Ar gases was investigated to effectively remove smear while minimizing via hole expansion. The desmear behavior was systematically analyzed as a function of via size and plasma gas composition using CCP-RIE equipment. Energy-dispersive X-ray spectroscopy (EDS) analysis identified Si-containing residues at the via bottom. The addition of Ar enhanced physical sputtering and improved smear removal efficiency. Focused ion beam–scanning electron microscopy analysis showed that the optimized dry desmear process effectively removed smear residues while suppressing hole expansion. Compared with the conventional wet desmear process, the plasma dry desmear achieved approximately 2 μm less hole expansion, which is critical for fine-pitch micro-via fabrication. These results demonstrate that plasma-assisted dry desmear provides a promising approach for next-generation high-density advanced packaging technologies. Sun, 01 Nov 2026 00:00:00 GMT https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/218613 2026-11-01T00:00:00Z https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/211536 Title: Nonlinear quantized conductance dynamics in vertical SiN RRAM for scalable memory-learning integration Authors: Park, Jihee; Kim, Nawoon; Na, Hyesung; Kim, Hyungjin; Kim, Sungjun Abstract: We report a vertical resistive random-access memory device based on a Pt/SiN/Ti stack, designed for multi-bit storage and neuromorphic computing. The device exhibits stable bipolar switching and achieves up to 7-bit (128-level) conductance states through precise control of compliance current and reset voltage. Quantized conductance plateaus, corresponding to integer and half-integer multiples of the quantum conductance G<inf>0</inf> = 2e2/h, reveal atomic-scale filament dynamics governed by nonlinear conduction processes. Diverse synaptic plasticity functions, including spike-number-, spike-rate-, spike-duration-, and spike-amplitude-dependent plasticity, were experimentally emulated. Neuromorphic simulations for the Modified National Institute of Standards and Technology dataset achieved classification accuracies exceeding 94 %, confirming the device's suitability for high-precision weight modulation. The vertical architecture ensures scalability toward three-dimensional integration, while robust retention and compatibility with current-based multi-bit modulation highlight its potential for complex-system-inspired edge AI and in-memory computing hardware. Tue, 01 Sep 2026 00:00:00 GMT https://scholarworks.bwise.kr/hanyang/handle/2021.sw.hanyang/211536 2026-09-01T00:00:00Z