Effects of substrate temperature on graphene grown on Ni foil via atmospheric pressure chemical vapor deposition

Abstract

Multilayer graphene was grown on Ni foil(30μm) via atmospheric pressure chemical vapor deposition (APCVD) at different temperature of 800°C,900°C,1000°C, we observe structural difference between the three process by in situ X-ray diffraction and Raman measurements, our experimental results show that temperature plays an important role on graphene growth, the growth rate is increased with the increasing temperature. Moreover, we found that at growth temperature of 900 , °C graphene has the best quality. These results will be helpful to better understanding the growth mechanism in the graphene growth process. Introduction Since its discovery,graphene has attracted more and more interest as apotential candidate for next generation electronic devices for its remarkable electronic properties, Many efforts have been made to produce graphene using a variety of method,suchas reduction of graphene oxide, chemical vapor deposition (CVD),mechanical exfoliation of highly oriented pyrolytic graphite (HOPG)and epitaxial growth on SiC substrates,To date,large-Area and high-qualitygraphene has been reported by CVD, which uses transition metalsubstrates, such as Cu and Ni as a catalyst to grow graphene. However, the growth mechanism of graphene on catalyst is still not very clear, it is necessary to studythe effect of substrate temperature on graphene grown. This paper present few layer graphene (FLG) growth on Ni foil(30μm) by CVD at three different temperature including 800°C,900°Cand 1000°C.X-ray diffraction(XRD) is a nondestructive method of characterization which can provide structure information ofthe interlayer spacing and strain,the whole experiment process was observed using in situ XRD in Shanghai Synchrotron Radiation Facility(SSRF). The surface structure information was also characterized by Raman spectroscopy.From these results,we found that temperature plays an important role in graphene growth and will affect the growth process, such as growth rateand crystalline quality. Experimental and results For in situ observation of the whole graphene growth,a home-built reactor consists of Mass-flow Controller (flowmeter), Vacuum pump, Temperature Controller,Water Cooling Circuitsand ,Vacuometer were prepared, Ni foil(30μm)with a purity>99.99% purchased from HeFeiKeJing Materials Technology Co.Ltd. was cutted into 1x1cm, and ultrasonic cleaned by acetone, absolute ethyl alcohol, deionized water for 5minutes respectively, Figure.1 shows the illustration of the graphene growth process and its different stages,the CVD chamber for graphene growth was pumped to approximately 400 Pa , then the Ni foil was heated up to 900°Cin 28 minutes for high temperature heat-treatment for15 minutes, at the same time, 180sccm H2(10%) /Ar and 60sccm Ar mixed gaswas introduced during the whole process until the heat treatment ends, the sample was heated up to or cool down to designated growth temperature, XRD equipment starts to collect data once 150sccm CH4, 10sccmH2mixed gas was introduced. CH4 was removed once the intensity of graphene peak(002) increased to a designated value, and replaced by 180sccm 2nd International Workshop on Materials Engineering and Computer Sciences (IWMECS 2015) © 2015. The authors Published by Atlantis Press 317