Structural and optoelectronic properties of dusty-plasma-grown Si:H films near the amorphous–nanocrystalline transition
Year: 2026
Type: article
Abstract: Nanocrystalline silicon (nc-Si:H) thin films were deposited by dusty-plasma PECVD under varying RF power and pressure conditions, with a focus on the amorphous-to-nanocrystalline transition. High deposition rates associated with the formation of conical growth morphology were achieved. Structural characterization shows that increasing the deposition parameters enhances the crystalline fraction. Raman spectroscopy indicates an increase in crystallite size, while AFM analysis reveals a distinct evolution of surface grain size, following the same trend as the deposition rate. Optical measurements demonstrate a decrease in both the absorption coefficient and refractive index with increasing crystalline fraction. The optical properties analyzed within the Wemple–DiDomenico framework reveal a clear inverse correlation between the average optical gap E M and the refractive index. Electrical characterization shows that charge transport remains dominated by localized states in the amorphous phase. The inverse correlation between activation energy and oxygen content, combined with hydrogen-related passivation effects at grain boundaries, indicates that O/H incorporation governs the effective conduction pathways. These findings pave the way for optimizing nc-Si:H thin films for advanced optoelectronic applications through precise control of growth conditions.
Source: Materials Today Communications
Institutions: Université Oran 1 Ahmed Ben Bella, University of Algiers Benyoucef Benkhedda, Centre de Développement des Technologies Avancées, University Yahia Fares of Medea, Université de Montpellier, Institut d'Électronique et des Systèmes, Saint Joseph University, Université de Rouen Normandie, Institut National des Sciences Appliquées Rouen Normandie
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $2,830
OpenAlex ID: W7160080280