METHOD FOR FORMING WIRE OF SEMICONDUCTOR DEVICE

PURPOSE: A method for forming a wire of a semiconductor device is provided to prevent the signal delay by reducing the capacitance between wires. CONSTITUTION: The first insulation film(22) is formed on a semiconductor substrate(20) formed with a lower wiring layer(21). A sacrificial layer for exposing the first insulation film(22) is formed on the first insulation film(22). Then, the second insulation film(24A) is coated on the first insulation film(22). A contact hole is formed by etching the second and first insulation films(24A,22). Then, a metal film is formed on the second insulation film(24A). After that, an upper wiring layer(26A) making contact with the lower wiring layer(21) is formed by a blanket etching process. The third insulation film(27A) is formed on the second insulation film(24A). Then, the third and second insulation films(27A,24A) are etched such that the sacrificial film pattern is exposed thereby forming a damascne structure. Then, the first insulation film(22) is exposed by removing the sacrificial film pattern. After that, the fourth insulation film(28) is formed so as to form an air gap between the damascne structure.