Method of fabricating dual damascene
AssigneeUnited Microelectronics Corp.
InventorsCheng-Yuan Tsai, Chih-Chien Liu, Juan-Yuan Wu
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Abstract
A method for fabricating dual damascene is to form an undoped silicate glass (USG) liner before forming a fluorinated silicate glass (FSG) layer which serves as an inter-metal dielectric (IMD) layer on a semiconductor substrate. As a result, the surface sensitivity is eliminated, while a FSG layer with a more uniform thickness and a higher reliability is obtained. In addition, the USG liner increases the adhesion between the FSG layer and other material layers, while no particles are easily formed thereon.
Claims14
A method for fabricating a dual damascene, comprising steps of:
- providing a substrate;
- forming a first undoped polysilicon glass (USG) liner on the substrate;
- forming a first fluorinated silicon glass (FSG) layer on the first USG liner;
- forming a stop layer having an opening on the first FSG layer, so that a part of the first FSG layer is exposed;
- forming a second USG liner to cover the stop layer and to fill the opening;
- forming a second FSG layer on the second USG liner;
- patterning the second USG liner and the second FSG layer using the stop layer as a stop to form a trench exposing a portion of the first FSG layer exposed by the stop layer;
- patterning the first FSG layer and the first USG layer exposed by the stop layer to form a via opening which exposes a part of a conductive layer.
A method for fabricating a inter-metal dielectric (IMD) layer, comprising steps of:
- providing a silicon nitride or silicon oxy-nitride layer;
- forming a USG liner on the silicon nitride or silicon oxy-nitride layer;
- and
- forming a FSG layer on the USG liner.
Dependencies are inferred from the claim text.