METHOD FOR FORMING PLUG OF SEMICONDUCTOR DEVICE

摘要

PURPOSE: A method for forming a plug of a semiconductor device is provided to prevent dishing by minimizing the difference of polishing selectivity between a polysilicon layer and an interlayer dielectric or a hard mask in CMP. CONSTITUTION: A gate stacked structure(100) including a gate(12) and a hard mask(13) is formed on a substrate(10). An interlayer dielectric is formed on the resultant structure. A contact hole is formed by selectively etching the interlayer dielectric. A polysilicon layer is filled in the contact hole. Self-silicon ion-implantation processing is performed to increase the content of silicon in the interlayer dielectric and the hard mask. A plug(16A) is then formed by CMP of the polysilicon layer.