Patent ID: 6368953
Filing Date: 2002-04-09
Classification: H01L

Abstract:
A method of fabricating an encapsulated metal structure in a feature formed in a substrate having a top surface, the feature having sidewalls and a bottom, the method comprising the steps of:depositing a first barrier layer on the top surface of the substrate and on the sidewalls and bottom of the feature; filling the feature with metal; forming a first recess in the metal, so that a top surface of the metal is lower than the top surface of the substrate, depositing a second barrier layer on the top surface of the metal; planarizing the first barrier layer and the second barrier layer so that the top surface of the substrate is exposed, a remaining portion of the second barrier layer is on the top surface of the metal and a portion of the top surface of the metal is exposed; forming a second recess in the metal at the exposed portion thereof, depositing a third barrier layer on the top surface of the metal and on the remaining portion of the second barrier layer, thereby filling the second recess in the metal; and planarizing the third barrier layer so that the top surface of the substrate is exposed and the metal is encapsulated by the first barrier layer, the second barrier layer and the third barrier layer.