Microstructure liner having improved adhesion

• US 6,380,628 B2
• Filed: 08/18/1999
• Issued: 04/30/2002
• Est. Priority Date: 08/18/1999
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Slattery, Jill, Wang, Yun-Yu, Miller, John A., Simon, Andrew, Uzoh, Cyprian E.
• Primary Examiner(s): Cao, Phat X.
• Application Number:
  US09/377,329
• Publication Number:
  US 20010019884A1
• Time in Patent Office: 986 Days
• Field of Search: 257/762, 257/763, 257/764, 257/765, 438/637, 438/675, 438/648, 438/665
• US Class Current: 257/762
• CPC Class Codes: H01L 21/76816 Aspects relating to the layout of the pattern or to the size of vias or trenches layout of the interconnections per se H01L23/528; CAD of ICs G06F30/00
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76862 Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76865 Selective removal of parts of the layer H01L21/76844 takes precedence
• CPC Class Codes: H01L 21/76871 Layers specifically deposited to enhance or enable the nucleation of further layers, i.e. seed layers

Abstract

A damascene structure, such as a conductive line or via, having a liner with a roughened surface between the substrate and the conductive fill and, preferably, a smooth bottom. The substrate underneath the liner may also have a roughened sidewall and smooth bottom. Such a structure provides enhanced adhesion between one or more layers of the damascene structure. The damascene structure may be manufactured by applying a photoresist over a substrate top surface, exposing the photoresist under conditions that create a standing wave in the resist, and developing the photoresist to provide a pattern having the desired roughened or serrated outline. The pattern is transferred into the substrate, the liner is applied over the substrate bottom and sidewalls, and the liner is filled with conductive material. A roughened liner surface may be achieved by applying a partial layer of liner material over the substrate, removing a portion of the partial layer, and repeating the application and removal steps.

Claims

1. A damascene structure disposed in an insulating substrate, wherein the substrate has a surface defining a first plane, the structure comprising:

a substrate sidewall extending in a second plane substantially perpendicular to the first plane;

a bottom extending in a third plane substantially parallel to the first plane;

a liner completely covering said sidewall and said bottom, said liner having a roughened surface with a regular serration pattern of alternating peaks and valleys extending in a plane parallel to the substrate surface; and

a conductive fill on said liner and in contact with said roughened surface of said liner.

2. The damascene structure of claim 1 wherein said roughened surface comprises two intersecting serration patterns.

3. The damascene structure according to claim 2 wherein said serration patterns intersect at substantially 90 degrees.

4. The damascene structure according to claim 1 wherein said roughened surface of said liner further comprises a serrated pattern along a cross section intersecting said substrate surface.

5. The damascene structure according to claim 1 wherein the sidewall has a roughened surface with a plurality of serrations in contact with said liner.

6. The damascene structure according to claim 5 wherein said substrate has a surface and said roughened sidewall surface comprises a serrated pattern along a longitudinal section parallel to said substrate surface.

7. The damascene structure of claim 5 wherein the bottom of said structure is smooth.

8. The damascene structure of claim 1 wherein said liner has a smooth surface over said bottom.

9. The damascene structure of claim 1 wherein the structure is one of a via and a line.

10. The damascene structure of claim 1 wherein the conductive fill is one of copper and aluminum.

11. The damascene structure of claim 1 wherein the liner is one of tantalum, titanium, and tungsten.

12. The damascene structure of claim 1 that is a bit line for a dynamic random access memory capacitor.