Hamsasew Hankebo Lemago , Soeun Choi Arwen , Dóra Hessz , Gyula Jágerszki , Petra Pál , Csaba Cserháti , Eszter Mónika Baradács , Tamás Fodor , Zoltán Erdélyi , Imre Miklós Szilágyi
{"title":"Thermal and plasma-enhanced ALD for the synthesis of inverse opal Al2O3 and its composite materials","authors":"Hamsasew Hankebo Lemago , Soeun Choi Arwen , Dóra Hessz , Gyula Jágerszki , Petra Pál , Csaba Cserháti , Eszter Mónika Baradács , Tamás Fodor , Zoltán Erdélyi , Imre Miklós Szilágyi","doi":"10.1016/j.vacuum.2025.114254","DOIUrl":null,"url":null,"abstract":"<div><div>This study explores the synthesis and characterization of inverse opal photonic crystals (IOPC) composed of Al<sub>2</sub>O<sub>3</sub> and its composites, coated with ultra-thin ZnO and TiO<sub>2</sub> layers using thermal atomic layer deposition (TALD) and plasma-enhanced ALD (PEALD). Polystyrene (PS) opal nanospheres (460 nm) served as a template on a silicon wafer. Al<sub>2</sub>O<sub>3</sub> was infiltrated into a PS opal template and subsequently calcined to remove the template. Ultra-thin ZnO and TiO<sub>2</sub> layers were deposited via TALD/PEALD to form composite IOPCs. Characterization by SEM/EDX, TG, UV–Vis spectroscopy, atomic force microscopy (AFM), photoluminescence (PL), and XPS confirmed the periodic, interconnected IO structures. The Al<sub>2</sub>O<sub>3</sub> IOPC demonstrated template removal and a reduced sphere diameter to ∼433 nm. Composite structures-maintained periodicity, with TALD yielding smoother surfaces compared to PEALD. The incorporation of ZnO and TiO<sub>2</sub> layers increased surface roughness. UV–Vis spectroscopy revealed absorption peaks at 275 nm for Al<sub>2</sub>O<sub>3</sub>, with additional peaks at 400 nm and 529 nm related to the photonic band gap and slow photon effects. XPS analysis reveals characteristic peaks for Al<sub>2</sub>O<sub>3</sub>, ZnO, and TiO<sub>2</sub>, along with oxygen vacancies and aluminum hydroxide formation, while elemental data highlight successful ZnO and TiO<sub>2</sub> incorporation with PEALD outperforming TALD in ZnO deposition. In this study PEALD enhanced film growth and tailored properties, while TALD offered smooth, conformal coatings and precise control over IOPC properties, both contributing to the design of advanced IO-based photonic materials.</div></div>","PeriodicalId":23559,"journal":{"name":"Vacuum","volume":"238 ","pages":"Article 114254"},"PeriodicalIF":3.8000,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Vacuum","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0042207X25002441","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
This study explores the synthesis and characterization of inverse opal photonic crystals (IOPC) composed of Al2O3 and its composites, coated with ultra-thin ZnO and TiO2 layers using thermal atomic layer deposition (TALD) and plasma-enhanced ALD (PEALD). Polystyrene (PS) opal nanospheres (460 nm) served as a template on a silicon wafer. Al2O3 was infiltrated into a PS opal template and subsequently calcined to remove the template. Ultra-thin ZnO and TiO2 layers were deposited via TALD/PEALD to form composite IOPCs. Characterization by SEM/EDX, TG, UV–Vis spectroscopy, atomic force microscopy (AFM), photoluminescence (PL), and XPS confirmed the periodic, interconnected IO structures. The Al2O3 IOPC demonstrated template removal and a reduced sphere diameter to ∼433 nm. Composite structures-maintained periodicity, with TALD yielding smoother surfaces compared to PEALD. The incorporation of ZnO and TiO2 layers increased surface roughness. UV–Vis spectroscopy revealed absorption peaks at 275 nm for Al2O3, with additional peaks at 400 nm and 529 nm related to the photonic band gap and slow photon effects. XPS analysis reveals characteristic peaks for Al2O3, ZnO, and TiO2, along with oxygen vacancies and aluminum hydroxide formation, while elemental data highlight successful ZnO and TiO2 incorporation with PEALD outperforming TALD in ZnO deposition. In this study PEALD enhanced film growth and tailored properties, while TALD offered smooth, conformal coatings and precise control over IOPC properties, both contributing to the design of advanced IO-based photonic materials.
期刊介绍:
Vacuum is an international rapid publications journal with a focus on short communication. All papers are peer-reviewed, with the review process for short communication geared towards very fast turnaround times. The journal also published full research papers, thematic issues and selected papers from leading conferences.
A report in Vacuum should represent a major advance in an area that involves a controlled environment at pressures of one atmosphere or below.
The scope of the journal includes:
1. Vacuum; original developments in vacuum pumping and instrumentation, vacuum measurement, vacuum gas dynamics, gas-surface interactions, surface treatment for UHV applications and low outgassing, vacuum melting, sintering, and vacuum metrology. Technology and solutions for large-scale facilities (e.g., particle accelerators and fusion devices). New instrumentation ( e.g., detectors and electron microscopes).
2. Plasma science; advances in PVD, CVD, plasma-assisted CVD, ion sources, deposition processes and analysis.
3. Surface science; surface engineering, surface chemistry, surface analysis, crystal growth, ion-surface interactions and etching, nanometer-scale processing, surface modification.
4. Materials science; novel functional or structural materials. Metals, ceramics, and polymers. Experiments, simulations, and modelling for understanding structure-property relationships. Thin films and coatings. Nanostructures and ion implantation.