Efficient growth of high-quality graphene films on Cu foils by ambient pressure chemical vapor deposition

The strong spin filtering effect can be produced by C-Ni atomic orbital hybridization in lattice-matched graphene/Ni (111) heterostructures, which provides an ideal platform to improve the tunnel magnetoresistance (TMR) of magnetic tunnel junctions (MTJs). However, large-area, high-quality graphene/ferromagnetic epitaxial interfaces are mainly limited by the single-crystal size of the Ni (111) substrate and well-oriented graphene domains. In this work, based on the preparation of a 2-inch single-crystal Ni (111) film on an Al2O3 (0001) wafer, we successfully achieve the production of a full-coverage, high-quality graphene monolayer on a Ni (111) substrate with an atomically sharp interface via ambient pressure chemical vapor deposition (APCVD). The high crystallinity and strong coupling of the well-oriented epitaxial graphene/Ni (111) interface are systematically investigated and carefully demonstrated. Through the analysis of the growth model, it is shown that the oriented growth induced by the Ni (111) crystal, the optimized graphene nucleation and the subsurface carbon density jointly contribute to the resulting high-quality graphene/Ni (111) heterostructure. Our work provides a convenient approach for the controllable fabrication of a large-area homogeneous graphene/ferromagnetic interface, which would benefit interface engineering of graphene-based MTJs and future chip-level 2D spintronic applications.

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Process Optimization for Synthesis of High-Quality Graphene Films by Low-Pressure Chemical Vapor Deposition

Japanese Journal of Applied Physics ◽

10.1143/jjap.51.06fd21 ◽

2012 ◽

Vol 51 ◽

pp. 06FD21

Author(s):

Dongheon Lee ◽

Kihwan Lee ◽

Saebyuk Jeong ◽

Juhyun Lee ◽

Bosik Choi ◽

...

Keyword(s):

Chemical Vapor Deposition ◽

Process Optimization ◽

Vapor Deposition ◽

Chemical Vapor ◽

Low Pressure ◽

High Quality ◽

Graphene Films ◽

Pressure Chemical

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Development of Vertical 3×2〞LPCVD System for Fast Epitaxial Growth on 4H-SiC

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.105 ◽

2012 ◽

Vol 717-720 ◽

pp. 105-108 ◽

Cited By ~ 2

Author(s):

Wan Shun Zhao ◽

Guo Sheng Sun ◽

Hai Lei Wu ◽

Guo Guo Yan ◽

Liu Zheng ◽

...

Keyword(s):

Growth Rate ◽

Chemical Vapor Deposition ◽

Epitaxial Growth ◽

Vapor Deposition ◽

Growth Process ◽

Chemical Vapor ◽

Low Pressure ◽

High Quality ◽

Pressure Chemical ◽

Homoepitaxial Layers

A vertical 3×2〞low pressure chemical vapor deposition (LPCVD) system has been developed to realize fast epitaxial growth of 4H-SiC. The epitaxial growth process was optimized and it was found that the growth rate increases with increasing C/Si ratio and tends to saturate when C/Si ratio exceeded 1. Mirror-like thick 4H-SiC homoepitaxial layers are obtained at 1500 °C and C/Si ratio of 0.5 with a growth rate of 25 μm/h. The minimum RMS roughness is 0.20 nm and the FWHM of rocking curves of epilayers grown for 1 hour and 2 hours are 26.2 arcsec and 32.4 arcsec, respectively. These results indicate that high-quality thick 4H-SiC epilayers can be grown successfully on the off-orientation 4H-SiC substrates.

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