A storage capacitor having a scattering effect is positioned in a substrate for use in a thin film transistor array loop. The storage capacitor is characterized by having a rough layer overlapped by a medium layer and a passivation layer. The storage capacitor further has a reflective layer with high reflectivity so as to provide the storage capacitor with the scattering effect toward an external light source. A method of manufacturing the storage capacitor by two photolithography processes is also shown.