METHOD FOR FABRICATING METAL LINE IN SEMICONDUCTOR DEVICE

摘要

A method for fabricating a metal line in a semiconductor device is provided to increase reliability and yield of a device so as to increase etch process margins. A method for fabricating a metal line in a semiconductor device includes the steps of: forming a bit line on a semiconductor substrate(21) defined at a cell and peripheral areas; forming a first interlayer insulating film(22) at an upper portion of the bit line; a first etch stopping layer(27) at an upper portion of the first interlayer insulating film; forming a capacitor in the cell area; forming a second etch stopping layer(31) at an upper portion of a total structure including the capacitor; forming a second interlayer insulating film(25) on the second etch stopping layer; forming a first contact hole opening an upper portion of the first etch stopping layer by etching the second interlayer insulating film and the second etch stopping layer; and forming a second contact hole exposing the bit line by etching the first etch stopping layer and the first interlayer insulating film. Further, CF4 as a main gas is used at the step of forming a second contact hole.