Two-stage growth for highly ordered epitaxial C$_{60}$ films on Au(111)

• Main Authors: Tully, Alexandra B, Greenwood, Rysa, Na, MengXing, King, Vanessa, Mårsell, Erik, Niu, Yuran, Golias, Evangelos, Mills, Arthur K, de Castro, Giorgio Levy, Michiardi, Matteo, Menezes, Darius, Yu, Jiabin, Zhdanovich, Sergey, Damascelli, Andrea, Jones, David J, Burke, Sarah A
• Format: Journal Article
• Language: English
• Published: 15-04-2024
• Subjects: Physics - Materials Science
• DOI: 10.48550/arxiv.2404.10053

As an organic semiconductor and a prototypical acceptor molecule in organic
photovoltaics, C$_{60}$ has broad relevance to the world of organic thin film
electronics. Although highly uniform C$_{60}$ thin films are necessary to
conduct spectroscopic analysis of the electronic structure of these
C$_{60}$-based materials, reported C$_{60}$ films show a relatively low degree
of order beyond a monolayer. Here, we develop a generalizable two-stage growth
technique that consistently produces single-domain C$_{60}$ films of
controllable thicknesses, using Au(111) as an epitaxially well-matched
substrate. We characterize the films using low-energy electron diffraction,
low-energy electron microscopy, scanning tunneling microscopy, and
angle-resolved photoemission spectroscopy (ARPES). We report highly oriented
epitaxial film growth of C$_{60}$/Au(111) from 1 monolayer (ML) up to 20 ML
films. The high-quality of the C$_{60}$ thin films enables the direct
observation of the electronic dispersion of the HOMO and HOMO-1 bands via ARPES
without need for small spot sizes. Our results indicate a path for the growth
of organic films on metallic substrates with long-range ordering.