METHOD OF FORMING METAL WIRING IN SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for metallization is to improve yields of a device by effectively removing a bridge fail generated due to a step difference of a wafer. CONSTITUTION: An interlayer dielectric(20) is formed on a semiconductor substrate(10) having a lower layer. After selectively etching the interlayer dielectric by an etching process using an etching mask, a contact hole is formed to expose a predetermined part of the semiconductor substrate. A tungsten layer(30) is deposited on the resultant structure. After polishing the tungsten layer until the interlayer dielectric is exposed through a CMP, a tungsten plug(30) is formed. Then, a BPSG layer(40) is formed on the resultant structure at a thickness of about 8000 angstroms to improve step coverage of a wafer. After selectively etching the BPSG layer to partially expose the tungsten plug and the interlayer dielectric, the first tungsten layer(50) is formed on the resultant structure. After polishing the first tungsten layer and the BPSG layer, the second tungsten layer(60) is formed.