A highly reliable capacitor, a semiconductor device having high operating performance and reliability, and a manufacturing method thereof are provided. A capacitor formed of a first conductive film 102, a dielectric 103 made of an insulating material, and a second conductive film 104 is characterized in that a pin hole 106 formed by chance in the dielectric 103 is filled up with an insulating material (filler) 107 made of a resin material. This can prevent short circuit between the first conductive film 102 and the second conductive film 104. The capacitor is used as a storage capacitor provided in a pixel of a semiconductor device.