Patent ID: 6812088
Filing Date: 2004-11-02
Classification: H01L

Abstract:
A method for making metal-insulator-metal (MIM) capacitors for CMOS circuits on a semiconductor substrate comprising the steps of:providing said semiconductor substrate having partially completed CMOS circuits including several levels of metal interconnections; depositing a first insulating layer and forming recesses for capacitor bottom metal (CBM) electrodes, pad contacts, and for a level of metal interconnections; depositing a conformal barrier layer on said first insulating layer and in said recesses; depositing a copper layer and polishing back to form said CBM electrodes, said pad contacts, and said level of metal interconnections in said recesses; depositing an insulating protecting buffer layer; depositing a second insulating layer on said insulating protecting buffer layer that serves as a portion of an interelectrode dielectric layer; depositing a conducting metal protect buffer layer on said second insulating layer; depositing a first photoresist layer and using a pad contact mask to expose and develop said first photoresist; plasma etching to etch pad contact openings and interconnect contact openings to said insulating protecting buffer layer, and removing said first photoresist layer; removing said insulating protecting buffer layer in said pad contact openings and said interconnect contact openings; depositing a blanket pad protection metal layer; using a second photoresist mask and plasma etching to pattern said blanket pad protection metal layer to form pad protection over said pad contacts, to form capacitor top metal (CTM) electrodes, and to form interconnecting lines; depositing a passivating third insulating layer; depositing a third photoresist layer and using said pad contact mask to expose and develop said third photoresist; plasma etching to form openings through said passivating third insulating layer to said pad protection over said pads and to said CTM electrodes, and removing said third photoresist.