Method of manufacturing a gap-filled structure of a semiconductor device

• US 20040211357A1
• Filed: 04/24/2003
• Published: 10/28/2004
• Est. Priority Date: 04/24/2003
• Status: Abandoned Application

• Current Assignee: Pradad N. Gadgil, Shmuel Erez
• Original Assignee: Pradad N. Gadgil, Shmuel Erez
• Inventors: Erez, Shmuel, Gadgil, Pradad N.
• Application Number:
  US10/422,760
• Publication Number:
  US 20040211357A1
• Time in Patent Office: Days
• US Class Current: 117/84
• CPC Class Codes: C23C 16/045 Coating cavities or hollow spaces, e.g. interior of tubes; Infiltration of porous substrates
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/54 Apparatus specially adapted for continuous coating
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76877 Filling of holes, grooves or trenches, e.g. vias, with conductive material

Abstract

This invention relates to process sequence by atomic layer chemical vapor processing that includes thin film deposition for diffusion barriers in the vias, trenches or contact plug-holes followed by gap fill with ALD/CVD process and subsequent removal of the blanket film on the top by Atomic Layer Processing/Chemical Vapor Processing. The processes can be carried out in separate chambers or may be combined into one or more chambers. The apparatus employed in these processing steps allows the practitioner to rapidly complete process sequences of barrier deposition, gap fill and top layer planarization. In case of copper metallization scheme, ALD gap fill can be employed to replace electrochemical deposition of copper. Atomic layer removal of copper and other blanket films by gas phase reactions can replace the chemical-mechanical-polishing of the blanket films. Additional advantages of such processing scheme are elimination of defects, dishing, erosion, corrosion, liquid-electrolyte, slurry and other liquid waste. Benefit of such a process scheme is entrapment of the effluents and also precise metering and control of the injected amount to affect the chemical reaction in each step of the sequence that can lead to significant savings and higher chemical utilization efficiency.

Claims

1. A method of filling a recess in a surface of an object comprising the steps of:

providing an atomic layer processing apparatus having a working chamber, at least a first chemical supply unit for the supply of a first chemical agent and a second chemical supply unit for the supply of a second chemical agent into said working chamber, said first chemical agent and said second chemical agent reacting with each other to produce a deposition material;

supplying said first chemical agent and said second chemical agent to said working chamber after said object is placed into said atomic layer processing apparatus;

causing a reaction between said first chemical agent and said second chemical agent for producing reaction products that contains said deposition material;

evacuating said working chamber for removing said reaction products except said deposition material;

depositing said deposition material into said recess by a process selected from atomic layer deposition and chemical vapor deposition for decomposing at least one of said first chemical agent and said second chemical agent in order to deposit said deposition material in the form of a deposited layer of a uniform thickness onto said surface and into said recess;

filling said recess by a process selected from continuously depositing said deposition material by said chemical vapor deposition and by repeating said step of depositing said deposition material by said atomic layer deposition process until said recess is completely filled, said deposited layer on said top surface having a thickness being substantially equal to half of said width of said recess.

2. The method of claim 1, further comprising the step of removing said deposited layer from said surface until said surface is exposed, said step of depositing and said step of removing being carried out in said atomic layer processing apparatus.

3. The method of claim 2, wherein said atomic layer processing apparatus is a first atomic layer processing apparatus, said object is a semiconductor device with a patterned dielectric layer on a substrate, said dielectric layer has a top surface;

said gap is completely filled with a conductive material, said gap having a width, said deposition material comprising said conductive material, said reaction causing decomposition of said at least one of said first chemical agent and said at least second chemical agent.

4. The method of claim 3, further comprising the following steps which are carried out prior to all steps of said claim 3:

providing a second atomic layer processing apparatus for processing a barrier-layer made from a barrier-layer material resistant to diffusion of said conductive material into said patterned dielectric layer, said second atomic layer processing apparatus having a barrier-layer processing chamber, at least a first barrier-layer chemical supply unit for the supply of a first barrier-layer chemical agent, and a second barrier-layer chemical supply unit for the supply of a second barrier-layer chemical agent into said barrier-layer processing chamber, said barrier layer having a barrier-layer thickness;

placing said substrate with said patterned dielectric layer into said second atomic layer processing apparatus for processing a barrier-layer;

supplying said first barrier-layer chemical agent and said second barrier-layer chemical agent to said barrier-layer processing chamber, causing a chemical reaction between said first barrier-layer chemical agent and said second barrier-layer chemical agent on the surface of said patterned dielectric layer for forming said barrier layer composed of a barrier layer material by atomic layer deposition;

repeating said step of forming said barrier layer until said barrier-layer thickness is achieved;

placing said substrate with said barrier layer on said pattern dielectric layer into said first atomic layer processing apparatus;

carrying out all steps of claim 3;

placing said substrate into said second atomic layer processing apparatus; and

removing said barrier layer from said top surface.

5. The method of claim 4, further comprising the steps of:

providing a third layer processing apparatus for processing a cap layer made from a cap layer material, said third layer processing apparatus having a cap layer processing chamber, at least a first cap layer chemical supply unit for the supply of a first cap layer chemical agent, and a second cap layer chemical supply unit for the supply of a second cap layer chemical agent into said cap layer processing chamber;

placing said substrate into said third layer processing apparatus after completion of said steps of claim 4 for forming said cap layer; and

supplying said first cap layer chemical agent and said second cap layer chemical agent to said cap layer processing chamber, causing a chemical reaction between said first cap layer chemical agent and said second cap layer chemical agent on said top surface of said dielectric layer, on said conductive material, and on said barrier layer.

6. The method of claim 5, comprising the steps of:

combining said first atomic layer processing apparatus, said second atomic layer processing apparatus, and said third atomic layer processing apparatus into a cluster machine provided with means for transferring said substrate between said first atomic layer processing apparatus, said second atomic layer processing apparatus, and said third atomic layer processing apparatus, and

performing said steps of claims 3, 4, and 5 with the use of said cluster machine, while performing said steps of placing said substrate into said first atomic layer processing apparatus, said second atomic layer processing apparatus, and said third atomic layer processing apparatus with the use of said means for transferring.

7. The method of claim 3, wherein said conductive material is selected from the group comprising copper and tungsten, said first chemical agent being selected for copper from a group comprising CuCl, Cu(II)(Hfac)₂, Cu(I)(hfac)tmvs, Cu(II)(thd)₂, for tungsten from a group comprising of WF₆, WCl₆, W(CO)₆, and said second chemical agent being selected for copper from the group comprising of H₂, .H, and for tungsten from the group comprising H₂, .H, .SiH₃.

8. The method of claim 4, wherein said conductive material is selected from the group comprising copper and tungsten, said first chemical agent being selected for copper from the group comprising of CuCl, Cu(II)(hfac)₂, Cu(I)(hfac)tmvs, Cu(II)((thd)₂, for tungsten from the group comprising of WF₆, WCl₆, W(CO)₆, said second chemical agent being selected for copper from the group comprising H₂, .H, and for tungsten from the group comprising of H₂, .H, .SiH₃;

said first barrier-layer chemical agent being selected from the group comprising of WF₆, TiCl₄, TiBr₄, Til₄,TaCl₅; and

said second barrier-layer chemical agent being selected from the group comprising of SiH₄, NH₃, CH₄, .NH₂, .CH₃, H₂, .H.

9. The method of claim 5, wherein said conductive material is copper, said first chemical agent being selected from the group comprising of CuCl, Cu(II)(hfac)₂, Cu(I)(hfac)tmvs, Cu(II)(thd)₂, said second chemical agent being selected from the group comprising of H₂, .H;

said first barrier-layer chemical agent being selected from the group comprising of WF₆, TiCl₄, TiBr₄, Til₄,TaCl₅;

said second barrier-layer chemical agent being selected from the group comprising of SiH₄, NH₃, CH₄, .NH₂, .CH₃, H₂, .H; and

said cap layer chemical agent being selected from the group comprising of SiH₄, NH₃, CH₄, .NH₂, .CH₃, H₂, .H.

10. The method of claim 4, comprising the steps of:

combining said first atomic layer processing apparatus and said second atomic layer processing apparatus into a cluster machine provided with means for transferring said substrate between said first atomic layer processing apparatus and said second atomic layer processing apparatus; and

performing said steps of claims 3 and 4 with the use of said cluster machine, while performing said steps of placing said substrate into said first atomic layer processing apparatus and said second atomic layer processing apparatus with the use of said means for transferring.

11. The method of claim 3, wherein said step of removal further comprises the steps of:

purging said working chamber of said second atomic layer processing apparatus after completing said step of filling said gap with said conductive material;

supplying a third chemical agent to said working chamber of said first atomic layer processing apparatus;

causing a reaction between said third chemical agent and said conductive material for producing an intermediate product of reaction on said conducive material, said intermediate product containing said conductive material;

supplying a fourth chemical agent to said working chamber of said first atomic layer processing apparatus;

causing a reaction between said fourth chemical agent and said intermediate product for producing a volatile product that contains said conductive material; and

removing said volatile material from said working chamber.

12. The method of claim 11, wherein said conductive material is selected from the group comprsing of copper and tungsten, said third chemical agent being selected for copper from the group comprising of O₂, Cl₂, Br₂, .O, .Cl, .Br, .OH, and for tungsten from .F, .Cl, .Br, and said fourth chemical agent being selected for copper from the group comprising of H⁺hfac, H⁺thd, tmvs.

13. The method of claim 4, wherein said step of removing said barrier layer from said top surface comprises the steps of:

purging said working chamber of said second atomic layer processing apparatus;

supplying at least one third barrier-layer chemical agent to said working chamber of said second atomic layer processing apparatus;

causing a reaction between said third barrier-layer chemical agent and said barrier layer for producing volatile products of reaction that contains said barrier-layer material; and

removing said volatile products from said working chamber of said second atomic layer processing apparatus.

14. The method of claim 13, wherein said third barrier layer chemical agent being selected from the group comprising of O₂, Cl₂, Br₂, .O, .Cl, .Br, and .F.