The optical properties of transferred graphene and the dielectrics grown on it obtained by ellipsometry

• Published in: Applied surface science Vol. 437; pp. 410 - 417
• Main Authors: Kasikov, Aarne, Kahro, Tauno, Matisen, Leonard, Kodu, Margus, Tarre, Aivar, Seemen, Helina, Alles, Harry
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.04.2018
• Subjects: Dielectrics; Graphene; Optical properties; PMMA; Spectroscopic ellipsometry; Dielectrics; Spectroscopic ellipsometry; PMMA; Graphene; Optical properties
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2017.08.109

[Display omitted] •The optical properties of the transferred graphene are found using spectroscopic ellipsometry.•SiO2 layer thickness on Si substrate is obtained together with graphene properties.•The quality of dielectric material on the top of graphene is characterized by optical methods. Graphene layers grown by chemical vapour deposition (CVD) method and transferred from Cu-foils to the oxidized Si-substrates were investigated by spectroscopic ellipsometry (SE), Raman and X-Ray Photoelectron Spectroscopy (XPS) methods. The optical properties of transferred CVD graphene layers do not always correspond to the ones of the exfoliated graphene due to the contamination from the chemicals used in the transfer process. However, the real thickness and the mean properties of the transferred CVD graphene layers can be found using ellipsometry if a real thickness of the SiO2 layer is taken into account. The pulsed laser deposition (PLD) and atomic layer deposition (ALD) methods were used to grow dielectric layers on the transferred graphene and the obtained structures were characterized using optical methods. The approach demonstrated in this work could be useful for the characterization of various materials grown on graphene.