Method for forming a semiconductor device with self-aligned contacts using a liner oxide layer

A method of manufacturing a semiconductor device on a semiconductor substrate, comprising:

• forming a multi-layer structure on an active region on the semiconductor substrate, wherein said multi-layer structure includes a floating gate, an inter-gate dielectric disposed on said floating gate, a control gate disposed on said inter-gate dielectric a silicide layer disposed on said control gate, and a top passivation layer disposed on said silicide layer, said top passivation layer comprises a material selected from the group consisting of nitride and oxynitride;
• forming a sidewall spacer around said multi-layer structure, wherein said sidewall spacer is of a nitride;
• forming a source region and a drain region on said active region adjacent said sidewall spacer;
• forming a liner oxide layer over the semiconductor substrate, including said multi-layer structure, said sidewall spacer, said source region and said drain region, said liner oxide layer in contact with said multi-layer structure, said sidewall spacer, said source region and said drain region, wherein said liner oxide layer includes silicon dioxide, and boron and phosphorus are absent;
• forming a dielectric layer over said liner oxide layer, said dielectric layer in contact with said liner oxide layer, wherein said dielectric layer includes boro-phospho-tetra-ethyl-ortho silicate (BPTEOS);
• and
• forming a contact extending through the dielectric layer and the oxide liner in contact with the top passivation layer and the sidewall spacer.