Method for fabricating semiconductor device and apparatus for fabricating same

• US 20010003064A1
• Filed: 12/04/2000
• Published: 06/07/2001
• Est. Priority Date: 12/02/1999
• Status: Abandoned Application

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Ohto, Koichi
• Application Number:
  US09/727,675
• Publication Number:
  US 20010003064A1
• Time in Patent Office: Days
• US Class Current: 438/687
• 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 21/3185 of siliconnitrides
• CPC Class Codes: H01L 21/76829 characterised by the formation of thin functional dielectric layers, e.g. dielectric etch-stop, barrier, capping or liner layers
• 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 21/76886 Modifying permanently or temporarily the pattern or the conductivity of conductive members, e.g. formation of alloys, reduction of contact resistances
• 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 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

A method for fabricating a semiconductor device wherein an interconnect made of copper overlying a substrate is pretreated at a specified temperature, for example, at 300° C. or less; and a dielectric film is formed on the copper at a temperature higher than that of the pretreatment. In accordance with the present invention, the adhesion between the copper and the dielectric film is improved by conducting the pretreatment of the dielectric film for reducing an oxide layer of the copper surface, and the agglomeration of the copper can be prevented by the pretreatment.

Claims

1. A method for fabricating a semiconductor device comprising the steps of:

forming an interconnect made of copper overlying a substrate;

conducting a pretreatment of the copper at 300°

C. or less; and

forming a dielectric film on the copper by a chemical vapor deposition method.

2. A method for fabricating a semiconductor device comprising the steps of:

forming an interconnect made of copper overlying a substrate;

conducting a pretreatment of the copper in a deposition chamber at a specified temperature; and

forming a dielectric film on the copper by a chemical vapor deposition method in the a deposition chamber at a temperature higher than the specified temperature.

3. The method as defined in

claim 2

, wherein the dielectric film includes SiN, SiC, SiCN and an organic film having a lower dielectric constant.

4. The method as defined in

claim 2

, wherein a wafer is exposed to a plasma atmosphere containing at least hydrogen for reducing copper oxide on a surface of the copper in the pretreatment.

5. The method as defined in

claim 2

, wherein a wafer is exposed to an atmosphere containing a reducing gas for reducing copper oxide on a surface of the copper in the pretreatment.

6. The method as defined in

claim 2

, wherein a gas for forming the pretreatment atmosphere includes NH₃ and N₂.

7. The method as defined in

claim 2

, wherein the copper includes a copper oxide layer which is removed in thepretreatment.

8. An apparatus for fabricating a semiconductor device comprising:

a deposition chamber for receiving a wafer having a copper interconnect layer thereon;

a mechanism for conducting a pretreatment on the wafer at a specified temperature; and

a mechanism for depositing a dielectric film on the copper interconnect layer at a temperature higher than the specified temperature.

9. The apparatus as defined in

claim 8

further comprising a lift pin and a susceptor, wherein the pretreatment of the wafer disposed on the lift pin is conducted without contact between the substrate and the susceptor.

10. The apparatus as defined in

claim 8

further comprising a jig for rapidly heating and rapidly cooling the wafer to conduct the pretreatment at the temperature lower than that of the film-formation.