METHOD FOR FORMING CONTACT OF SEMICONDUCTOR DEVICE TO PREVENT VIA CONTACT DEFECT

摘要

PURPOSE: A method for forming a contact of a semiconductor device is provided to prevent a via contact defect by avoiding an undercut phenomenon or a black via phenomenon caused by a chemical material in a lower metal interconnection layer. CONSTITUTION: The first metal layer(20) is formed on a semiconductor substrate(10). A capping layer composed of a Ti/TiN layer is formed on the first metal layer. An interlayer dielectric pattern(30A) having a contact hole for exposing a part of the upper surface of the capping layer is formed on the capping layer. The organic material remaining on the resultant structure is eliminated by a strip process using a mixture solution in which ammonia, acetic acid and pure water are mixed. The capping layer exposed through the contact hole is removed by a dry etch method using a mixture gas including Ar and BCl3 to expose a part of the upper surface of the first metal layer. A barrier metal layer(50) is formed on the sidewall and upper surface of the interlayer dielectric pattern and on the upper surface of the exposed first metal layer. The second metal layer(60) is formed on the resultant structure including the barrier metal layer to fill the contact hole.