Method for forming copper-containing metal studs
AssigneeIMEC vzx
InventorsRoger Palmans, Joost Waeterloos, Gibert Declerck
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Abstract
The method of the present invention is related to the fabrication of a copper-based multilevel interconnect structure. This copper-based multilevel interconnect structure is based on the formation of vertical metal connections through copper-containing metal stud growth on an underlying horizontal metal pattern, followed by a stud encapsulation step against copper diffusion into the surrounding dielectric, i.e. the insulating layers. This method is of particular interest when the insulating layers used to obtain this interconnect structure are polymer layers with a low dielectric constant and preferably with a high degree of planarization.
Claims10
A method for forming Cu-containing metal studs comprising the steps of:
- a) depositing a resist layer on a conductive pattern;
- b) patterning said resist layer by a sequence of at least one lithographic and at least one removal step to thereby form an opening in said resist layer, said opening extending down to the surface of said conductive pattern;
- c) depositing at least one Cu-containing metal to fill up said opening;
- and
- d) removing said resist layer to thereby free the Cu-containing metal stud formed on said conductive layer
- e) encapsulating said Cu-containing metal stud by depositing a barrier layer.
A method for forming an interconnect structure comprising the steps of:
- a) depositing a resist layer on a conductive pattern;
- b) patterning said resist layer by a sequence of at least one lithographic and at least one removal step to thereby form an opening in said resist layer, said opening extending down to the surface of said conductive pattern;
- c) depositing a Cu-containing metal to fill up said opening;
- d) removing said resist layer to thereby free the Cu-containing metal stud formed on said conductive layer;
- e) encapsulating said Cu-containing metal stud;
- f) depositing an insulating layer, said insulating layer covering said stud;
- g) forming a patterned hard mask layer on said insulating layer;
- and
- h) etching said insulating layer using said patterned hard mask layer as a mask to form an opening at least down to the surface of said encapsulated Cu-containing metal stud.
Dependencies are inferred from the claim text.