METHOD OF INTEGRATED SUBSTRATED PROCESSING USING A HOT FILAMENT HYDROGEN RADICAL SOUCE

• US 20080081464A1
• Filed: 09/29/2006
• Published: 04/03/2008
• Est. Priority Date: 09/29/2006
• Status: Abandoned Application

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Tokyo Electron Limited
• Inventors: Matsuda, Tsukasa, Sakuragi, Isamu
• Application Number:
  US11/537,573
• Publication Number:
  US 20080081464A1
• Time in Patent Office: Days
• US Class Current: 438/660
• CPC Class Codes: H01L 21/02063 the processing being the formation of vias or contact holes
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76814 post-treatment or after-treatment, e.g. cleaning or removal of oxides on underlying conductors
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric

Abstract

A method of integrated processing is provided for a substrate in the substrate processing tool. The substrate contains an etch feature in a dielectric film and an exposed metal interconnect pattern formed underneath the etch feature. The integrated process includes pretreating exposed surfaces of the etch feature and the exposed metal interconnect pattern with a flow of hydrogen radicals generated by thermal decomposition of H₂ gas by a hot filament hydrogen radical source separated from the substrate by a showerhead plate containing gas passages facing the substrate. The integrated process further includes depositing a barrier metal film over the pretreated exposed surfaces, and forming a Cu metal film on the barrier metal film.

Claims

1. A method of integrated substrate processing in a substrate processing tool, comprising:

providing a substrate containing an etch feature in a dielectric film, wherein a metal interconnect pattern formed underneath the etch feature is exposed; and

performing an integrated process on the substrate in the substrate processing tool, the process comprising;

pretreating exposed surfaces of the etch feature and the exposed metal interconnect pattern with a flow of hydrogen radicals generated by thermal decomposition of H₂ gas by a hot filament hydrogen radical source separated from the substrate by a showerhead plate containing gas passages facing the substrate;

depositing a barrier metal film over the pretreated exposed surfaces; and

forming a Cu metal film on the barrier metal film.

2. The method of claim 1, wherein the etch feature comprises a trench, a via, or a combination thereof.

3. The method of claim 1, wherein the pretreating terminates the exposed surfaces of the dielectric film with hydrogen.

4. The method of claim 1, wherein the pretreating reduces a metal oxide layer of the exposed metal interconnect pattern to the corresponding metal.

5. The method of claim 4, wherein the exposed metal interconnect pattern comprises Cu.

6. The method of claim 1, wherein the H₂ gas is mixed with an inert gas.

7. The method of claim 1, wherein the depositing a barrier metal film comprises

depositing a Ta-containing film over the pretreated exposed surfaces.

8. The method of claim 7, wherein the depositing a Ta-containing film comprises

depositing a TaN or TaCN film.

9. The method of claim 7, wherein the depositing a Ta-containing film comprises

depositing a TaN or TaCN film, and

depositing a Ta film over the TaN or TaCN film.

10. The method of claim 7, wherein the depositing a barrier metal film further comprises

depositing a Ru film over the Ta-containing film.

11. The method of claim 1, wherein the forming a Cu metal film comprises

depositing a Cu seed layer over the barrier metal film, and

plating a bulk Cu film onto the Cu seed layer.

12. The method of claim 10, wherein the forming a Cu metal film comprises

plating bulk Cu onto the Ru film.

13. The method of claim 1, wherein the pretreating comprises

maintaining a temperature of a metal wire filament in the hot filament hydrogen radical source at a temperature between 1200°

C. and 2500°

C.

14. The method of claim 1, wherein the pretreating comprises

maintaining a temperature of a metal wire filament in the hot filament hydrogen radical source at a temperature between 1400°

C. and 1600°

C.

15. The method of claim 1, wherein the pretreating comprises

maintaining the substrate at a temperature between room temperature and 500°

C.

16. The method of claim 1, wherein the etch feature comprises a trench and a via, each having a sidewall and a bottom, the method further comprising

removing the barrier metal film substantially completely from the bottom of the via and at least partially from the bottom of the trench by sputter etching prior to the forming a Cu metal film.

17. The method of claim 1, wherein the depositing a barrier metal film comprises

depositing a W-containing film or a Ti-containing film over the pretreated exposed surfaces.

18. The method of claim 1, wherein the hydrogen radicals substantially comprise neutral hydrogen radicals.

19. The method of claim 1, wherein the pretreating, depositing, and any intervening steps are performed without exposing the substrate to air.

20. A method of integrated substrate processing in a substrate processing tool, comprising:

providing a substrate containing an etch feature in a dielectric film, the etch feature comprising a trench having a sidewall and a bottom, a via at the bottom of the trench, the via having a sidewall and a bottom, and a Cu interconnect pattern exposed at the bottom of the via; and

performing an integrated process on the substrate in the substrate processing tool, the process comprising;

pretreating exposed sidewall and bottom surfaces of the etch feature and the exposed Cu interconnect pattern with a flow of hydrogen radicals generated by thermal decomposition of H₂ gas by a hot filament hydrogen radical source separated from the substrate by a showerhead plate containing gas passages facing the substrate;

depositing a barrier metal film over the pretreated exposed sidewall and bottom surfaces, wherein the pretreating, depositing, and any intervening steps are performed without exposing the substrate to air, and the barrier metal film comprises a Ta-containing film and a Ru metal film over the Ta-containing film; and

forming a Cu metal film on the barrier metal film by depositing a Cu seed layer over the Ru metal film and plating a bulk Cu film onto the Cu seed layer.

21. The method of claim 20, further comprising

removing the barrier metal film substantially completely from the bottom of the via and at least partially from the bottom of the trench by sputter etching prior to the forming a Cu metal film.