Paper by H. Okcu
The paper "Multi-head spatial atomic layer deposition: a robust approach for precise doping and nanolaminate fabrication in open-air environments" has been published in Nanoscale
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Here you will find the paper by the H. Okcu
"Open-air manufacture of functional nanolaminates demands rapid and scalable methods that maintain nanoscale precision across individual layers. Conventional spatial atomic layer deposition (SALD) employs a single deposition head, and the concurrent exposure to mutually reactive precursors does not provide precise layer thickness accuracy nor sharp interfaces. This work addresses these challenges with an innovative multi-head SALD design. In this study, we introduced a novel multi-head SALD system comprising a uniform head for depositing 5 nm zinc oxide (ZnO) sublayers, while a combinatorial high-throughput head delivered wedge-like thickness gradient in aluminum oxide (Al2O3) sublayers, increasing gradually from 0 to approximately 6 nm along the substrate. Eight ZnO/Al2O3 bilayers (320 ALD cycles per material) were completed in open air at 200 °C. Transmission electron microscopy recorded highly sharp and reproducible layer-to-layer structures with thickness deviations of 0.3 nm; X-ray photoelectron spectroscopy verified the absence of undesirable aluminum contamination in the reference ZnO regions. With increasing Al2O3 thickness, surface roughness was reduced from 0.58 to 0.33 nm, ZnO (002) reflections broadened as crystallite size was confined, and Kelvin probe measurements showed a shift in work function values from 4.75 to 4.35 eV with Al2O3 passivation. This study demonstrates that the multi-head SALD method offers a robust platform for achieving precise multilayer control in open-air conditions, thereby paving the way for further innovations in materials research through optimized experimental conditions and combinatorial approaches.."
"Open-air manufacture of functional nanolaminates demands rapid and scalable methods that maintain nanoscale precision across individual layers. Conventional spatial atomic layer deposition (SALD) employs a single deposition head, and the concurrent exposure to mutually reactive precursors does not provide precise layer thickness accuracy nor sharp interfaces. This work addresses these challenges with an innovative multi-head SALD design. In this study, we introduced a novel multi-head SALD system comprising a uniform head for depositing 5 nm zinc oxide (ZnO) sublayers, while a combinatorial high-throughput head delivered wedge-like thickness gradient in aluminum oxide (Al2O3) sublayers, increasing gradually from 0 to approximately 6 nm along the substrate. Eight ZnO/Al2O3 bilayers (320 ALD cycles per material) were completed in open air at 200 °C. Transmission electron microscopy recorded highly sharp and reproducible layer-to-layer structures with thickness deviations of 0.3 nm; X-ray photoelectron spectroscopy verified the absence of undesirable aluminum contamination in the reference ZnO regions. With increasing Al2O3 thickness, surface roughness was reduced from 0.58 to 0.33 nm, ZnO (002) reflections broadened as crystallite size was confined, and Kelvin probe measurements showed a shift in work function values from 4.75 to 4.35 eV with Al2O3 passivation. This study demonstrates that the multi-head SALD method offers a robust platform for achieving precise multilayer control in open-air conditions, thereby paving the way for further innovations in materials research through optimized experimental conditions and combinatorial approaches.."