▎ 摘　　要

NOVELTY - The carbon thin film (1) contains graphene (1a) . The edge portion (1E) of graphene is exposed in the main surface (1S) of carbon thin film. USE - For working electrode of electron sources (both claimed) used for display devices such as field emission display and biosensor. Also used for working electrode for electrochemistry, lithium ion battery and as hydrogen storage material. ADVANTAGE - High electrically active carbon thin film is provided, since the edge portion of graphene has high activity. The biochip comprising the carbon thin film has high detection sensitivity. The electron source comprising the carbon thin film effectively discharges electron by low electric field. DETAILED DESCRIPTION - The carbon thin film is provided on a porous oxide film containing alumina (12) that is formed by anodic oxidation of aluminum. INDEPENDENT CLAIMS are included for the following: (1) electron source comprising carbon thin film in the electron-emission portion; (2) working electrode containing carbon thin film; and (3) manufacture of carbon thin film. DESCRIPTION OF DRAWING(S) - The figures show the perspective diagram and sectional drawing of substrate at which carbon thin film is formed. carbon thin film (1) graphite (1A) graphene (1a) edge portion (1E) main surface (1S) alumina (12)