Abstract: An object of the present invention is to provide a method for manufacturing a substrate having a metal complex film on the surface thereof. According to the present invention, a metal salt-containing composition containing a metal salt, a polyvalent carboxylic acid having a cis-form structure, and a solvent, in which: the molar ratio of the polyvalent carboxylic acid to the metal salt is not less than 0.5 and not more than 4.0; the moisture content of the composition is not less than 0.05% by weight is used in an application method to apply on a substrate. Thereafter, a two-step heat treatment is carried out.

Abstract: The present invention achieves a formation of a metal oxide film of a thin film transistor with a simplified process. The present invention is concerned with a method for manufacturing a field-effect transistor comprising a gate electrode, a source electrode, a drain electrode, a channel layer and a gate insulating layer wherein the channel layer is formed by using a metal salt-containing composition comprising a metal salt, a polyvalent carboxylic acid having a cis-form structure of —C(COOH)?C(COOH)—, an organic solvent and a water wherein a molar ratio of the polyvalent carboxylic acid to the metal salt is in the range of 0.5 to 4.0.

Abstract: The present invention achieves a formation of a metal oxide film of a thin film transistor with a simplified process. The present invention is concerned with a method for manufacturing a field-effect transistor comprising a gate electrode, a source electrode, a drain electrode, a channel layer and a gate insulating layer wherein the channel layer is formed by using a metal salt-containing composition comprising a metal salt, a polyvalent carboxylic acid having a cis-form structure of —C(COOH)?C(COOH)—, an organic solvent and a water wherein a molar ratio of the polyvalent carboxylic acid to the metal salt is in the range of 0.5 to 4.0.

Abstract: An object of the present invention is to provide a metal salt-containing composition which is applicable to many metal source materials, and can be used for forming a compact and uniform metal oxide film comparable to those formed according to a sputtering method, as well as to provide a substrate having a metal complex film on the surface thereof obtained using the metal salt-containing composition, and a substrate having a metal complex film on the surface thereof obtained by further heating the substrate. Moreover, another object of the present invention is to provide a method for manufacturing a substrate having such a metal complex film on the surface thereof. According to the present invention, a metal salt-containing composition containing a metal salt, a polyvalent carboxylic acid having a cis-form structure, and a solvent, in which: the molar ratio of the polyvalent carboxylic acid to the metal salt is not less than 0.5 and not more than 4.