| 摘要 |
A process for avoiding dishing in a planarizing layer whose final thickness is reduced by Chem. Mech. Polishing, is described. The first step is to coat the surface to be planarized with a layer of a hard dielectric material, such as silicon nitride, prior to depositing the planarizing medium. After the latter has been reflowed, its thickness is reduced by means of CMP. While CMP is being applied, the etch rate is constantly sensed. When the etch front approaches the aforementioned hard layer a decrease in the etch rate is sensed and etching is terminated, thereby eliminating any dishing effects.
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