Ultrathin multilayer metal alloy liner for nano Cu interconnects

• US 10,643,890 B2
• Filed: 05/10/2016
• Issued: 05/05/2020
• Est. Priority Date: 06/08/2014
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Edelstein, Daniel, Grill, Alfred, Knupp, Seth L., Nguyen, Son, Nogami, Takeshi, Paruchuri, Vamsi K., Shobha, Hosadurga K., Yang, Chih-Chao
• Primary Examiner(s): Garber, Charles D
• Assistant Examiner(s): Sabur, Alia
• Application Number:
  US15/151,230
• Publication Number:
  US 20160276280A1
• Time in Patent Office: 1,456 Days
• CPC Class Codes: C23C 16/04 Coating on selected surface areas, e.g. using masks
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/16 from metal carbonyl compounds
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/30 Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45544 characterized by the apparatus
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: C23C 16/54 Apparatus specially adapted for continuous coating
• CPC Class Codes: C23C 16/56 After-treatment
• 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 21/28562 Selective deposition
• CPC Class Codes: H01L 21/28568 the conductive layers comprising transition metals H01L21/28518 takes precedence
• CPC Class Codes: H01L 21/76802 by forming openings in dielectrics
• CPC Class Codes: H01L 21/76831 in via holes or trenches, e.g. non-conductive sidewall liners
• 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 21/7684 Smoothing; Planarisation
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76849 the layer being positioned on top of the main fill metal
• CPC Class Codes: H01L 21/7685 : the layer covering a conductive structure H01L21/76849 takes precedence
• CPC Class Codes: H01L 21/76852 : the layer also covering the sidewalls of the conductive structure
• CPC Class Codes: H01L 21/76862 : Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76864 : Thermal treatment
• CPC Class Codes: H01L 21/76879 : by selective deposition of conductive material in the vias, e.g. selective C.V.D. on semiconductor material, plating plating on semiconductors in general H01L21/288
• CPC Class Codes: H01L 21/76883 : Post-treatment or after-treatment of the conductive material
• CPC Class Codes: H01L 23/5226 : Via connections in a multilevel interconnection structure
• CPC Class Codes: H01L 23/528 : Geometry or layout of the interconnection structure H01L27/0207 takes precedence; algorithms G06F30/00
• CPC Class Codes: H01L 23/53238 : Additional layers associated with copper layers, e.g. adhesion, barrier, cladding layers
• 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

Compositions of matter, compounds, articles of manufacture and processes to reduce or substantially eliminate EM and/or stress migration, and/or TDDB in copper interconnects in microelectronic devices and circuits, especially a metal liner around copper interconnects comprise an ultra thin layer or layers of Mn alloys containing at least one of W and/or Co on the metal liner. This novel alloy provides EM and/or stress migration resistance, and/or TDDB resistance in these copper interconnects, comparable to thicker layers of other alloys found in substantially larger circuits and allows the miniaturization of the circuit without having to use thicker EM and/or TDDB resistant alloys previously used thereby enhancing the miniaturization, i.e., these novel alloy layers can be miniaturized along with the circuit and provide substantially the same EM and/or TDDB resistance as thicker layers of different alloy materials previously used that lose some of their EM and/or TDDB resistance when used as thinner layers.

Claims

1. An interconnect structure, comprising:

a semiconductor substrate;

a dielectric layer on the semiconductor substrate;

a trench within the dielectric layer;

a copper wire layer within the trench, the copper wire layer having a top surface;

a metal alloy liner within the trench and between the dielectric layer and the copper wire layer, the metal alloy liner having a thickness between about 0.1 nm to about 3.0 nm and comprising Co/Mn/W, W/Mn or W/Mn/Co; and

a metal alloy cap on the top surface of the copper wire layer, the metal alloy cap comprising Co/Mn/W, W/Mn or W/Mn/Co.

2. The interconnect structure of claim 1, further including a copper seed layer between the metal alloy liner and the copper wire layer.

3. The interconnect structure of claim 2, wherein the dielectric layer is an interlevel dielectric layer comprising a low-k dielectric material.

4. The interconnect structure of claim 2, wherein the metal alloy liner comprises Mn, W and/or Co in the following amounts:

Mn, about 0.1 to about 20 parts by weight;

Co, 0 to about 100 parts by weight;

W, 0 to about 100 parts by weight.

5. The interconnect structure of claim 2, further including a dielectric cap on the metal alloy cap.

6. The interconnect structure of claim 2, wherein the metal alloy cap comprises Mn, W and/or Co in the following amounts:

Mn, about 0.1 to about 20 parts by weight;

Co, 0 to about 100 parts by weight;

W, 0 to about 100 parts by weight.

7. The interconnect structure of claim 1, wherein the metal alloy liner comprises Co/Mn/W or W/Mn/Co.

8. The interconnect structure of claim 1, wherein the metal alloy cap comprises Co/Mn/W or W/Mn/Co.

9. The interconnect structure of claim 1, further including a second metal alloy cap on a top surface of the metal alloy cap on the top surface of the copper wire layer, the second metal alloy cap comprising Co/Mn/W or W/Mn/Co.