Patent ID: 6410422
Filing Date: 2002-06-25
Classification: H01L

Abstract:
A method of forming contact openings having different depths and different opening sizes, comprising:providing a substrate, wherein a plurality of devices is formed on the substrate; forming a liner layer to cover the devices; forming a dielectric layer at least having a first depth and a second depth over the liner layer; forming a photoresist layer over the dielectric layer to expose locations of contact openings; performing a one-step etching process using a C5F8/CO/O2/Ar etching gas and using the liner layer as an etching stop to etch the dielectric layer exposed by the photoresist layer, wherein after the etching process, a local interconnect contact opening, a share contact opening, and a borderless opening are formed to expose the liner layer, both the local interconnect opening and the share contact opening have a first depth and a second depth, an opening size of the local interconnect opening is larger than an opening size of the share contact opening, and an opening size of the share contact opening is larger than an opening size of the borderless opening; removing the liner layer exposed by the local interconnect opening, the share contact opening, the borderless contact opening to exposes the devices; and removing the photoresist layer.