Chemical vapor deposition of graphene on prepatterned catalyst
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Nanotechnology (MPNAT), MSc
Publicerad
Författare
Lin, Xiaotian
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
This thesis explores the growth of high-mobility monolayer graphene on copper
foils using Chemical Vapor Deposition (CVD), focusing on the influence of surface morphology and grain size of the copper substrate. Graphene’s exceptional
electrical, thermal, and mechanical properties make it a promising material for various advanced electronic applications, particularly in the development of graphene
field-effect transistors (GFETs). However, achieving high-quality graphene with uniformity and minimal defects remains a significant challenge, primarily due to the
variations in the copper substrate’s surface characteristics.
In this work, we investigate the correlation between the copper foil’s surface morphology and grain size and the quality of the graphene produced. The study employs
low-pressure CVD (LPCVD) with methane as the carbon source, and hot-wall thermal CVD to precisely control the deposition environment. Key factors such as the
copper substrate’s crystallinity, smoothness, and catalytic properties are analyzed
to optimize the growth process. The self-limiting nature of graphene growth on
copper, facilitated by copper’s low carbon solubility, is leveraged to achieve uniform
monolayer graphene.
This project also includes the prepatterning method as one of the ways of controlling the alignment of nuclei, which is done based on maskless photo-lithography. By
using prepatterning, patterned oxidation on copper foils can be achieved, the nucleation of graphene during CVD growth can only happen on the open areas where
there’s no oxide layer, which controls the position of nuclei.
Furthermore, this research aims to enhance the copper substrate preparation methods to improve graphene’s mobility and overall quality, thus making it more viable
for large-scale production. The outcomes of this study could contribute to advancing
the scalability of high-performance graphene for industrial applications, particularly
in the field of nanoelectronics.