Method of forming a dram crown capacitor

A method of forming a DRAM capacitor, comprising the following steps in the sequence set forth:

• forming a first silicon oxide layer on a substrate;
• forming a nitride layer on said first silicon oxide layer;
• patterning said nitride layer and said first silicon oxide layer to form a contact hole through said nitride layer and said first silicon oxide layer to said substrate;
• filling polysilicon into said contact hole;
• removing a top part of said polysilicon in said contact hole to form a blank part of said contact hole;
• filling W-metal (selective tungsten metal) in said blank part of said contact hole;
• forming a second silicon oxide layer on surfaces of said nitride layer and said W-metal (selective tungsten metal);
• patterning said second silicon oxide layer to form a trench, and said W-metal (selective tungsten metal) being exposed in said trench;
• forming a barrier metal layer on surfaces of said trench and said second silicon oxide layer and contact with said W-metal;
• forming a first metal layer on said barrier metal layer;
• forming a photo resist on said first metal layer;
• removing said photo resist, said first metal layer and said barrier metal layer on said second silicon oxide layer by planarization, then removing said photo resist in said trench to expose said first metal layer;
• forming a dielectric layer on said first metal layer and said second silicon oxide layer;
• and
• forming a second metal layer on said dielectric layer.