The present invention achieves the enhancement of stability of operational performance of a display device and the enlargement of margin of design in circuit designing. In a semiconductor device including a semiconductor, a gate insulation film which is brought into contact with the semiconductor, a gate electrode which faces an active layer by way of the gate insulation film, a first inorganic insulation film which is formed above the active layer, an SOG film which is formed on the first inorganic insulation film, and a second inorganic insulation film which is formed on the SOG film, and wiring which is formed on the second inorganic insulation film, an inner wall surface of a first opening portion formed in the SOG film is covered with the second inorganic insulation film and, at the same time, a second opening portion which is formed in a laminated body including the gate insulation film, the first inorganic insulation film and the second inorganic insulation film is provided to the inside of the first opening portion, and the semiconductor and the wiring are connected to each other through the first opening portion and the second opening portion.