शुक्रवार, 19 अप्रैल 2024

Improving the quality of graphene/Cu by Joule heating and enabling polymer-free direct transfer onto arbitrary substrates

U. Mogera and G. U. Kulkarni
Carbon, 124, 525-530 (2017)

 

Graphene grown on Cu surfaces by chemical vapour deposition is not always of the quality required for device fabrication. Here we report, a method involving Joule heating of the Cu substrate carrying graphene in ordinary vacuum so as to improve its quality. Under optimized conditions of current and time, there was significant improvement in the Raman features of graphene; the I2D/IG improved two to three times the value of as-obtained graphene. Additionally, extraneous growths were removed and the crystallinity improved thus enabling facile etching away of Cu without the aid of any polymer film support. The free-standing graphene transferred onto SiO2/Si substrate exhibited high field effect mobility value.

Posted by Dr. Umesha Mogera