Thin film transistor, liquid crystal display using thin film transistor, and method of manufacturing thin film transistor

A method of manufacturing a thin film transistor comprising the steps of:

• forming a gate electrode on an insulating substrate;
• forming a semiconductor film and a conductive film on said insulating substrate and on said gate electrode with interposing a gate insulating film between both said insulating substrate and said gate electrode, and said semiconductor film;
• forming a photo-resist film above said semiconductor film and above said conductive film;
• patterning said conductive film and said semiconductor film by use of said photo-resist film as a mask and thereby forming a conductive film and a semiconductor film in island shapes;
• forming a source electrode and a drain electrode isolated from each other by patterning said conductive film;
• and
• subjecting said semiconductor film between said source electrode and said drain electrode to channel etching,
• wherein irregularities are formed on both edges of said semiconductor film provided
• along extending direction and in a direction orthogonal to the extending direction, and
• a concave portion of the irregularities is located outside a region sandwiched by a pair of virtual straight lines linking both ends of opposite edges of said source electrode and said drain electrode.