| abstract |
A thin-film transistor (TFT) has a gate insulating film excellent in transparency and flatness. The gate insulating film is formed by a transparent insulating film ( 131 ) which is composed of an oxide represented by R x MO y and which is arranged between a gate electrode and a semiconductor layer. The transparent insulating film ( 131 ) is made of a coating agent which is composed of one mixed liquid obtained by dissolving or dispersing a condensate, which is obtained by subjecting a compound represented by R x MX m-x (where R represents a non-hydrolyzable substituent, M represents Si, Ti, Al, Zr, Zn, Sn or In, X represents a hydrolyzable substituent, x represents an integer of 0-3, and m represents the valence of M) to a hydrolysis-condensation reaction, in an organic solvent, water or their mixed solvent, or alternatively a coating agent which is obtained by mixing two or more of such mixed liquids. |