▎ 摘　　要

NOVELTY - Semiconductor device comprises a graphene film (12) disposed on a substrate (10) and formed of atomic layers (22) of graphene that are stacked, a source electrode (14) and a drain electrode (16) disposed on the graphene film, and a gate electrode (18) disposed between the source and drain electrodes with a gate insulator film interposed between the gate electrode and graphene film. The first number of the atomic layers in a source region where the source electrode is located and in a drain region of the drain electrode is greater than a second number in a channel region. The gate electrode is also located in the drain region. USE - Semiconductor device. ADVANTAGE - The contact resistance between the source electrode and the graphene film is reduced, and the parasitic resistance is reduced. The transistor characteristics such as cutoff frequency deteriorate is prevented from deteriorating. The semiconductor device has high electron mobility and high cutoff frequency. The parasitic resistance of the source and drain electrodes is reduced and the cutoff frequency of the transistor is improved. The characteristics of the semiconductor devices are improved, since the contact resistance is low between the gate electrode and graphene film and between the drain and source electrodes and the gate insulator film is low. Since the number of the atomic layers of graphene film in the source region and the drain region where the drain electrode is located is greater than the second number of atomic layers in the channel region, the characteristics of transistor are improved. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a method of manufacturing a semiconductor device, which involves: (a) forming a first silicon carbide (SiC) film on a substrate; (b) forming a first graphene film having an atomic layer of graphene from the first SiC film by heat-treating the first SiC film; (c) forming a second SiC film in a portion of a region on the first graphene film; (d) forming a second graphene film having an atomic layer of graphene from the second SiC film by heat-treating the second SiC film; (e) forming a gate electrode on the first graphene film in a region where the second graphene film is not formed with a gate insulator film interposed between the gate electrode and the first graphene film; and (f) forming a source electrode and a drain electrode on the second graphene film at respective sides of the gate electrode. DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional view of a semiconductor device. Substrate (10) Graphene film (12) Source electrode (14) Drain electrode (16) Gate electrode (18) Aatomic layers od graphene (22)