Self-aligned metal electrode to eliminate native oxide effect for metal insulator semiconductor (MIS) capacitor

A method of forming a capacitor, comprising the steps:

• providing a substrate including a capacitor area isolated by shallow trench isolation structures formed within shallow trench isolation structure trenches;
• forming an inchoate capacitor on the substrate within the capacitor area whereby portions of the substrate separate the inchoate capacitor from the shallow trench isolation structures;
• forming a first dielectric layer over the substrate, the shallow trench isolation structures and the inchoate capacitor;
• patterning the first dielectric layer to:
• form a patterned first dielectric layer portion masking the inchoate capacitor;
• and
• expose at least portions of the shallow trench isolation structures and the substrate portions separating the inchoate capacitor from the shallow trench isolation structures;
• forming tungsten portions at least over the substrate portions;
• forming a second dielectric layer over the patterned first dielectric layer portion, the tungsten portions and the shallow trench isolation structures whereby the tungsten portions formed at least over the substrate portions prevent formation of native oxide on at least the substrate portions;
• and
• completing formation of the capacitor.