Removable inorganic anti-reflection coating process

A method for employing and removing inorganic anti-reflection coatings, comprising the steps of:

• providing a substrate having deep trenches formed thereon and a pad stack formed thereon, the trenches including storage nodes and buried straps formed in the trenches;
• providing a first dielectric layer on a semiconductor device structure to be processed, the first dielectric layer being selectively removable relative to the semiconductor device structure;
• forming an inorganic dielectric anti-reflection coating (DARC) on the first dielectric layer, the DARC being selectively removable relative to the first dielectric layer;
• patterning a resist layer on the DARC, the resist layer being selectively removable relative to the DARC;
• etching the semiconductor device structure;
• and
• selectively removing the resist layer, the DARC and the first dielectric layer;
• wherein the first dielectric layer comprises a portion that forms an overhang structure on a vertical surface of the semiconductor device to prevent at least some coverage of the vertical surface by the DARC.

A method for employing inorganic anti-reflection coatings, comprising the steps of:

• providing a substrate having deep trenches formed thereon and a pad stack formed thereon, the trenches including storage nodes and buried straps formed in the trenches;
• providing a first dielectric layer on a semiconductor device structure to be processed, the first dielectric layer being selectively removable relative to the semiconductor device structure;
• forming an inorganic dielectric anti-reflection coating (DARC) on the first dielectric layer, the DARC being selectively removable relative to the first dielectric layer;
• patterning a resist layer on the DARC, the resist layer being selectively removable relative to the DARC;
• etching a portion of the DARC and the first dielectric layer in accordance with the resist layer;
• selectively removing the resist layer with respect to the DARC;
• and
• etching the semiconductor device structure by employing the DARC as a hard mask.