▎ 摘　　要

NOVELTY - Graphene sheet comprises 1-20 graphene layers, and has 2D band/G band intensity ratio of greater than or equal to 0.4, where peak of the 2D band appears at the position of greater than or equal to 2680 cm-1, and peak of the G band appears at position of less than or equal to 1596 cm-1 when measuring Raman spectra. The peak of the G band appears at position of 1580-1596 cm-1. USE - The graphene sheet is useful for electronic device (claimed). ADVANTAGE - The graphene sheet is high-quality graphene sheet having few defects even at low temperature of less than or equal to 1300 degrees C and large diameter, and improves performance of the electronic device. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for electronic device comprising a channel layer comprising graphene sheet, a source electrode and a drain electrode respectively contacting both ends of the channel layer, a gate insulating layer located on the channel layer, and a gate electrode disposed on the gate insulating layer.