Patent ID: 6096655
Filing Date: 2000-08-01
Classification: H01L

Abstract:
A method for forming trenches and vias in a single step in an inter-insulation layer for a dual damascene structure with via and trench heights, without etching out the inter-insulation layer, comprising the steps of:depositing a first sacrificial layer to the height of vias;etching said sacrificial layer to form sacrificial pillars in a location of said vias;depositing a first inter-insulation layer planarized with tops of said sacrificial pillars;depositing a second sacrificial layer over said first inter-insulation layer to the height of a trench;etching said second sacrificial layer to form a sacrificial bridge in a location of said trench;depositing a second inter-insulation layer on said first inter-insulation layer planarized with said sacrificial bridge; andselectively etching said sacrificial bridge and said sacrificial pillars to form said trench and vias in a single step.