Patent ID: 6358850
Filing Date: 2002-03-19
Classification: B24B,H01L

Abstract:
A method of polishing an oxide topographic feature on a substrate by slurry-less chemical-mechanical polishing, said method comprising:a) providing a substrate having an oxide material layer on a first surface, the oxide material layer having portions which have a height differential relative to each other, the height being measured from a reference plane parallel with a principal plane of the substrate, b) providing a first aqueous liquid medium containing a cationic surfactant, c) contacting the oxide material layer of the substrate with the first aqueous liquid medium and with a polishing member, the polishing member containing a fixed abrasive component therein, d) maintaining the contact of step c) while providing movement between the substrate and polishing member, whereby the height differential becomes reduced, and e) providing a second aqueous liquid medium different from the first medium, the second medium being alkaline, f) contacting the oxide layer resulting from step d) with the second aqueous liquid medium and with a polishing member, the polishing member containing an abrasive component fixed therein, and g) maintaining the contact of step f) while providing movement between the substrate and polishing member, whereby the oxide layer becomes reduced in thickness.