Chemical vapor deposition of graphene on copper at reduced temperatures

Abstract

A preliminary study on reduced temperature chemical vapor deposition of graphene on copper substrates was performed. Graphene’s exceptional mechanical strength, very high electrical and thermal conductivity, and stability at atomic layer thicknesses, generates potential for a broad range of applications, from nanodevices to transparent conductor to chemical sensor. Of the techniques demonstrated for graphene formation, chemical vapor deposition is the sole process suitable for manufacturing large area lms. While large area lm deposition of graphene has been shown on metal substrates, this process has been limited to high temperatures, 900-1000C, which increases the cost of production and limits methods of integrating the graphene with other material structures. In this work, CVD of graphene on copper foil was attempted over a range of temperatures (650 - 950C) on substrates as large as 5 x 15 cm in a horizontal tube reactor. Depositions were performed using both CVD and upstream Plasma-Enhanced CVD (PECVD), and the results are compared for both techniques. Quality of graphene lms deposited with and without plasma enhancement was characterized by micro Raman spectroscopy.