METHOD FOR FORMING BIT LINE OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a bit line of a semiconductor device is provided to prevent the top notch and line groove of a hard mask by capping the hard mask using an USG(Undoped Silicon Glass) oxide layer. CONSTITUTION: After a hard mask material layer is formed at the upper portion of a bit line conductive material layer(100), a hard mask(200) is formed by selectively patterning the hard mask material layer. A nitride layer(300) is formed at the upper portion of the resultant structure. An oxide layer(400) is formed at the upper portion of the nitride layer. The oxide layer is selectively removed for exposing the nitride layer by carrying out a post cleaning process. The exposed nitride layer is removed. A bit line is completed by selectively etching the bit line conductive material layer by using the hard mask and the remaining oxide layer as an etching mask.