▎ 摘　　要

NOVELTY - The device has first BCN layer (2a) that is inserted between a first graphene (1a) and a second graphene (1b). A second BCN layer (2b) is inserted between the second graphene and a third graphene (1c). The first graphene, the second graphene and the third graphene, and first and second BCN layers are arranged on a plane. A base electrode (4) is formed through an insulating film on second graphene. USE - Semiconductor device such as graphene transistor. ADVANTAGE - The reliable semiconductor device which combines the high mobility characteristic of the graphene and low leakage current is realizable. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a manufacturing method of semiconductor device. DESCRIPTION OF DRAWING(S) - The drawing shows a perspective view of the graphene transistor. (Drawing includes non-English language text) Graphenes (1a-1c) BCN layer (2a,2b) Emitter electrode (3) Base electrode (4) Collector electrode (5)