▎ 摘　　要

NOVELTY - Preparation of reduced and N-doped graphene oxide (4), comprises: (a) preparing the mixed solution containing graphene oxide and tetramethylammonium hydroxide; and (b) heating the mixed solution. USE - The method is useful for preparation of reduced and N-doped graphene oxide, used in a transistor (claimed) including FET. ADVANTAGE - The method: does not require any additional additive: is simple and pro-environmental method; and provides mass production of reduced and N-doped graphene oxide at low temperatures in cost-effective manner. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a transistor (100) which is located on top of the reduced and N-doped graphene oxide prepared by the method, in the structure composed of a gate electrode (3), a gate insulator (1) on top of the gate electrode, a semiconductor oxide (2) on top of the gate insulator, and the reduced and N-doped graphene oxide on top of the semiconductor oxide, and contains a source electrode and a drain electrode facing each other. DESCRIPTION OF DRAWING(S) - The figure illustrates the transistor containing the reduced and N-doped graphene oxide. Gate insulator (1) Semiconductor oxide (2) Gate electrode (3) Reduced and N-doped graphene oxide (4) Transistor (100)