▎ 摘　　要

NOVELTY - The gate electrode provided on the channel region consisting of graphite thin film or carbon nanotube, which is formed on the substrate (11), controls the carrier concentration of the channel region. A voltage application device changes the polarity of the transistor, from the direction of gate electrode. USE - Bipolar FET e.g. bipolar graphene channel FET used in semiconductor integrated circuit device (claimed) such as common-source circuit used in phase modulator, gate circuit e.g. two-input gate circuit used for designing digital circuits, logic circuit, etc. ADVANTAGE - By controlling the polarity of the bipolar FET, various functions can be obtained and high functionalization of the integrated circuit device is achieved. Improvement in the operating speed, size reduction and cost reduction of the chip are obtained. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for semiconductor integrated circuit device. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic sectional drawing of the bipolar FET. (Drawing includes non-English language text) Substrate (11) Insulating film (12) Graphene film (13) Source electrode (14) Gate insulating film (16)