PURPOSE: To make it possible to realize high-reliability and high-density wiring by applying a liquid type photosensitive polyimide comprising components the same as those of a sheet-like photosensitive polyimide to a substrate with a wiring pattern already formed and by laminating the sheet-like photosensitive polyimide on the substrate.

CONSTITUTION: Lower wiring 2 is formed on the substrate 1 such as ceramics; and a liquid photosensitive polyimide having the same composition as a sheet- like photosensitive polyimide 3 is applied. By doing this, the liquid photosensitive polyimide 3 having fluidity smoothens the projected and recessed portions on the substrate 1 formed by the lower wiring 2. Next, a sheet-like photosensitive polyimide 4 is laminated and this well follows the surface of substrate 1 and will not take in air. Thereafter, a photolithography opening 5 is formed and the openings 5 can be made at the same time because both the liquid photosensitive polyimide 3 and sheet-like photosensitive polyimide 4 have the same composition. Then, the upper wiring 6 is formed.