Multilayer integrated circuit copper plateable barriers

• US 6,900,127 B2
• Filed: 08/27/2003
• Issued: 05/31/2005
• Est. Priority Date: 08/27/2003
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Grunow, Stephan, Papa Rao, Satyavolu S., Russell, Noel M.
• Primary Examiner(s): NGUYEN, THANH T
• Application Number:
  US10/649,256
• Publication Number:
  US 20050048776A1
• Time in Patent Office: 643 Days
• Field of Search: 438/650, 438/678, 438/680, 438/681, 438/686, 438/687
• US Class Current: 438/678
• CPC Class Codes: H01L 21/2855 by physical means, e.g. sputtering, evaporation H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76862 Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76873 for electroplating

Abstract

A trench (70) is formed in a dielectric layer (20). A first metal layer (80) is formed in the trench using physical vapor deposition. A second metal layer (100) is formed in the trench (70) over the first metal layer (80) using chemical vapor deposition. Copper (110) is used to fill the trench (70) by electroplating copper directly onto the second metal (100).

Claims

1. A method for forming integrated circuit copper lines, comprising:

forming a trench in a dielectric layer;

forming a first metal layer in said trench using physical vapor deposition and a high atomic number metal wherein said high atomic number metal is selected from a group consisting of Ruthenium, Iridium, and Rhodium;

forming a second metal layer in said trench contacting on said first metal layer using chemical vapor deposition and a high atomic number metal wherein said high atomic number metal is selected from a group consisting of Ruthenium, Iridium, and Rhodium; and

filling said trench with copper by electroplating copper directly on said second metal layer.

2. The method of claim 1 wherein said forming a first metal layer in said trench comprises forming a Ruthenium layer using a plasma excitation power of 100 to 1000 watts with a DC power of 5 KW to 30 KW applied to a sputter metal target.

3. The method of claim 1 wherein said forming a second metal layer in said trench comprises flowing a vapor containing Ruthenium over a surface heated to between 100°

C. and 350°

C.

4. The method of claim 1 further comprising forming a third metal layer in said trench contacting on said second metal layer using chemical vapor deposition and a metal selected from a group consisting of Ruthenium, Iridium, and Rhodium.

5. The method of claim 4 further comprising forming a fourth metal layer in said trench contacting said third metal layer using chemical vapor deposition and a high atomic number metal.