METHOD FOR FORMING POLYSILICON PLUG USING CHEMICAL MECHANICAL POLISHING

摘要

PURPOSE: A polysilicon plug formation method is provided to remove particles between cell region and peripheral region and prevent a short between adjacent plugs by using CMP(chemical mechanical polishing). CONSTITUTION: The method comprises the steps of: forming a plurality of contact holes by selective etching an interlayer dielectric(14) formed on a silicon substrate(11); depositing a polysilicon on the entire surface of the resultant structure; a first CMP the resultant structure to expose the surface of the interlayer insulator(14) using a first slurry having quick polishing speed of the polysilicon compared to the insulator; and a second CMP the resultant structure using a second slurry having similar polishing speed between the insulator and the polysilicon.