abstract |
A method of planarizing wide dielectric filled isolation trenches formed in the surface of a semiconductor surface is described. A self aligned mask is formed on the thick conformal layer of dielectric in the depressions over the wide trenches to protect the dielectric in those trenches from etching during planarization steps. The mask material is chosen to have etch characteristics different from the dielectric layer and a subsequent planarizing organic layer to allow selective etching of the mask material or dielectric without etching the other materials in the structure. |