Aluminum is used as a material of wiring in various electronic devices such as a solar cell, a semiconductor device, and an electronic display device. Heretofore, it has generally been practiced to form such an aluminum film by a vacuum process such as a sputtering, vacuum deposition or chemical vapor deposition (CVD) method and to form a pattern by a photoetching method. Since this method requires a large-scale vacuum deposition device, not only is it disadvantageous in terms of energy consumption, but it is also difficult to uniformly form aluminum wiring on a substrate having a large surface area, resulting in poor yield and one of the causes of high costs.
In contrast, there has recently been proposed the technology in which a solution composition containing a complex of an amine compound and an aluminum hydride, and an organic solvent is applied on a substrate and then an aluminum film is formed by heating the solution composition (specification of Japanese Patent No. 3,817,201). This technology is an excellent technology which can form a satisfactory quality aluminum film by a simple method without requiring a massive and heavy apparatus. However, since this technology requires a pretreatment in which an organometallic compound of Ti, Pd or Al is applied on a substrate and then subjected to a heat treatment before application of the solution composition, the technology has such a drawback that a film made of an oxide of the metal is interposed in the space between the thus formed aluminum film and the substrate, thus failing to ensure electrical bonding between the substrate and the aluminum film.