INTERCONNECTS HAVING SEALING STRUCTURES TO ENABLE SELECTIVE METAL CAPPING LAYERS

• US 20150097292A1
• Filed: 12/12/2014
• Published: 04/09/2015
• Est. Priority Date: 06/03/2005
• Status: Active Grant

• Current Assignee: Tahoe Research Limited (f/k/a Learndale Limited) (Vector Capital Corporation)
• Original Assignee: Intel Corporation
• Inventors: HE, Jun, FISCHER, Kevin J., ZHOU, Ying, MOON, Peter K.
• Granted Patent: US 9,437,545 B2
• Time in Patent Office: Days
• US Class Current: 257/768
• CPC Class Codes: H01L 21/0217 the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz H01L21/02126 and H01L21/0214 take precedence
• CPC Class Codes: H01L 21/02252 formation by plasma treatment, e.g. plasma oxidation of the substrate after treatment of an insulating film by plasma H01L21/3105 and subgroups
• CPC Class Codes: H01L 21/32053 of metal-silicide layers
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76834 formation of thin insulating films on the sidewalls or on top of conductors H01L21/76831 takes precedence
• CPC Class Codes: H01L 21/76844 Bottomless liners
• CPC Class Codes: H01L 21/76849 the layer being positioned on top of the main fill metal
• CPC Class Codes: H01L 21/76856 by treatment in plasmas or gaseous environments, e.g. nitriding a refractory metal liner
• CPC Class Codes: H01L 21/76865 Selective removal of parts of the layer H01L21/76844 takes precedence
• CPC Class Codes: H01L 21/76877 Filling of holes, grooves or trenches, e.g. vias, with conductive material
• CPC Class Codes: H01L 21/76888 By rendering at least a portion of the conductor non conductive, e.g. oxidation
• CPC Class Codes: H01L 23/5283 Cross-sectional geometry
• CPC Class Codes: H01L 23/53209 based on metals, e.g. alloys, metal silicides H01L23/53285 takes precedence
• CPC Class Codes: H01L 23/53228 the principal metal being copper
• CPC Class Codes: H01L 23/53238 Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/53266 Additional layers associated with refractory-metal layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 23/5329 Insulating materials
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

Methods of fabricating a capped interconnect for a microelectronic device which includes a sealing feature for any gaps between a capping layer and an interconnect and structures formed therefrom. The sealing features improve encapsulation of the interconnect, which substantially reduces or prevents electromigration and/or diffusion of conductive material from the capped interconnect.

Claims

1. A method of fabricating an interconnect structure, comprising:

providing an interconnect including a conductive material extending into a dielectric material layer;

forming capping layer proximate said interconnect; and

forming a sealing structure to seal at least one gap of exposed interconnect conductive material between said capping layer and said dielectric layer.

2. The method of claim 1, wherein forming the sealing structure comprises:

exposing the exposed interconnect conductive material to silane to form a first salicide layer; and

exposing the first salicide layer to an ammonia source to form a silicon nitride layer.

3. The method of claim 2, wherein forming the sealing structure comprises:

exposing an exposed surface of the capping layer to silane to form a second salicide layer; and

exposing the second salicide layer to the ammonia source to form the silicon nitride layer.

4. The method of claim 3, wherein said sealing structure comprises the silicon nitride layer that is different than the capping material layer.

5. The method of claim 3, wherein the first silicide layer is formed at a different rate than the second silicide layer.

8. The apparatus of claim 3, wherein the sealing structure comprises the silicon nitride layer that is different than the capping material layer.

6. An apparatus comprising:

an interconnect including a conductive material extending into a dielectric material layer;

a capping layer proximate the interconnect; and

a sealing structure adapted to seal at least one gap of exposed interconnect conductive material between the capping layer and the dielectric layer by exposing the exposed interconnect conductive material to silane to form a first salicide layer and exposing the first salicide layer to an ammonia source to form a silicon nitride layer.

7. The apparatus of claim 6, wherein the silicon nitride layer includes a second salicide layer that is formed by exposing an exposed surface of the capping layer to silane to form the second salicide layer which is exposed to the ammonia source to form the silicon nitride layer.

9. A method of fabricating an interconnect structure, comprising:

providing a dielectric material layer;

forming an opening within said dielectric material layer;

forming a barrier material layer on at least one sidewall and bottom of said opening;

disposing a conductive material within said opening and abutting said barrier material layer;

forming capping layer proximate said conductive material; and

forming a sealing structure to seal at least one gap of exposed conductive material between said capping layer and said dielectric layer.

10. The method of claim 9, wherein forming said sealing structure comprises forming a salicide in portions of a conductive material of said interconnect by exposure to silane and exposing said salicide to an ammonia source to form a silicon nitride layer.

11. The method of claim 9, wherein the sealing structure comprises the silicon nitride layer that is different than the capping material layer.