▎ 摘　　要

NOVELTY - The transistor (100) has a gate electrode (120) formed on a silicon substrate (110). A gate insulating layer (130) is formed on the gate electrode. A graphene channel (140) is formed on the layer. A source electrode (151) and a drain electrode (152) are formed on the channel, where the source and the drain electrode are separated from each other. A cover (160) covers upper surfaces of the source and the drain electrode. The cover forms an air gap (170) above the channel between the source electrode and the drain electrode. The cover is formed of a porous polymer/ porous insulating material. USE - Graphene transistor for use as a radio frequency transistor in a hybrid transistor (claimed). ADVANTAGE - The transistor increases mobility of a graphene channel by forming an air gap over the graphene channel. The transistor reduces the reduction in the mobility of the graphene channel due to impurities on a surface of the gate insulating layer when the gate insulating layer is formed of hexagonal boron nitride. DETAILED DESCRIPTION - The gate insulating layer is formed of hexagonal boron nitride. INDEPENDENT CLAIMS are also included for the following: (1) a hybrid transistor comprising a metal-oxide-semiconductor transistor (2) a method for fabricating a hybrid transistor. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic cross-sectional view of a graphene transistor. Graphene transistor (100) Silicon substrate (110) Insulating layer (112, 122) Gate electrode (120) Gate insulating layer (130) Graphene channel (140) Source electrode (151) Drain electrode (152) Cover (160) Air gap (170)