@article{oh_thelven_margavio_parsons_2024, title={Low-Temperature Dual-Material Area-Selective Deposition: Molybdenum Hexafluoride-Mediated SiO<sub>2</sub> Fluorination/Passivation for Self-Aligned Molybdenum/Metal Oxide Nanoribbons}, volume={4}, ISSN={["1616-3028"]}, url={https://doi.org/10.1002/adfm.202316872}, DOI={10.1002/adfm.202316872}, abstractNote={Abstract Area‐selective deposition (ASD) is a forefront nanopatterning technique gaining substantial attention in the semiconductor industry. While current research primarily addresses single‐material ASD, exploring multi‐material ASD is essential for mitigating complexity in advanced nanopatterning. This study describes molybdenum hexafluoride (MoF 6 )‐mediated fluorination/passivation of the hydroxylated SiO 2 (SiO 2 ‒OH) at 250 °C as a new method to pacify nucleation during subsequent ZnO and TiO 2 atomic layer deposition (ALD). In contrast, Al 2 O 3 ALD is not passivated on the fluorinated SiO 2 (SiO 2 ‒F). The study further shows that Mo ALD using MoF 6 and silane (1 wt% SiH 4 in Ar) selectively proceeds on hydrogen‐terminated Si (Si‒H), whereas SiO 2 ‒OH becomes fluorine‐passivated without observable Mo deposition. This enables subsequent ZnO and TiO 2 ASD on Mo versus SiO 2 ‒F, as confirmed by X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and scanning transmission electron microscopy (STEM). Proposed growth and inhibition mechanisms highlight the importance of the metal oxide precursor in achieving selectivity. Taken together, self‐aligned Mo/ZnO and Mo/TiO 2 nanoribbons are demonstrated on coplanar nanoscale Si‒H/SiO 2 ‒OH patterns by sequentially integrating two individual ASD processes: 1) Mo ASD on Si‒H versus SiO 2 ‒OH; and 2) ZnO or TiO 2 ASD on Mo versus SiO 2 ‒F. This work highlights the potential for this approach in new ASD systems.}, journal={ADVANCED FUNCTIONAL MATERIALS}, author={Oh, Hwan and Thelven, Jeremy M. and Margavio, Hannah R. M. and Parsons, Gregory N.}, year={2024}, month={Apr} }
 @article{oh_kim_margavio_parsons_2023, title={Self-Aligned Nanopatterning and Controlled Lateral Growth by Dual-Material Orthogonal Area-Selective Deposition of Poly(3,4-ethylenedioxythiophene) and Tungsten}, volume={35}, ISSN={["1520-5002"]}, url={https://doi.org/10.1021/acs.chemmater.3c00530}, DOI={10.1021/acs.chemmater.3c00530}, abstractNote={Despite recent advances in area-selective deposition (ASD) processes, most studies have focused on single-material ASD. Multi-material ASD processes could provide additional flexibility for fabricating semiconductor devices. In this work, we identify process requirements to sequentially combine two intrinsic ASD processes: (1) poly(3,4-ethylenedioxythiophene) (PEDOT) ASD on SiO2 vs Si–H via oxidative chemical vapor deposition and (2) W ASD on Si–H vs SiO2 via atomic layer deposition. Using ex situ X-ray photoelectron spectroscopy, we show that a preferred orthogonal ASD sequence involves PEDOT ASD on SiO2 vs Si–H, followed by W ASD on Si–H vs PEDOT. We find that the properties of the individual PEDOT and W ASD materials, including resistivity, surface roughness, and growth rate, are affected by the ASD sequence. Furthermore, we successfully demonstrate that orthogonal ASD can be extended to nanoscale starting patterns. The cross-sectional scanning transmission electron microscopy (STEM) with energy-dispersive X-ray spectroscopy analysis shows that the resulting PEDOT thickness on SiO2 depends on feature geometry and dimension. Finally, we demonstrate the feasibility that the PEDOT layer can control the lateral growth of W onto the non-growth surface.}, number={11}, journal={CHEMISTRY OF MATERIALS}, author={Oh, Hwan and Kim, Jung-Sik and Margavio, Hannah R. M. and Parsons, Gregory N.}, year={2023}, month={May}, pages={4375–4384} }
 @article{kim_oh_parsons_2022, title={Growth behavior and substrate selective deposition of polypyrrole, polythiophene, and polyaniline by oxidative chemical vapor deposition and molecular layer deposition}, volume={40}, ISSN={["1520-8559"]}, url={https://doi.org/10.1116/6.0002036}, DOI={10.1116/6.0002036}, abstractNote={Bottom-up self-aligned area-selective deposition (ASD) plays an important role in patterning of advanced electronic devices. Specifically, ASD of organic materials can be utilized for nucleation inhibitors, sacrificial layers, and air-gap materials for next-generation nanoscale processing. This work introduces fundamental growth behavior of various conjugated polymers including polypyrrole, polythiophene, and polyaniline via oxidative molecular layer deposition and chemical vapor deposition. Effects of process parameters on film properties are described, and ASD behavior of different polymers are quantitatively characterized. These findings expand fundamental understanding of conjugated polymer deposition and provide new perspectives for ASD of organic thin films.}, number={6}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A}, author={Kim, Jung-Sik and Oh, Hwan and Parsons, Gregory N.}, year={2022}, month={Dec} }