In a step for forming a contact through hole in a protective film that covers a Thin Film Transistor (TFT) to connect a source electrode of the TFT and a pixel electrode to each other, location of a later-formed contact through hole is designed to be apart not less than 2.0 &mgr;m from location of the opening of an overcoat layer, which opening is formed on the protective film. This construction forces the opening of a novolac type photosensitive resist to be positioned inside the location of the opening of the overcoat layer and therefore, the contact through hole formed in the protective film is able to have a tapered cross sectional profile that is never affected by the opening of the overcoat layer, allowing for stable connection between the source electrode and the pixel electrode.