SEMICONDUCTOR TECHNOLOGY

Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics

Shengli Wang1, , Kangda Yin1, 2, , Xiang Li1, Hongwei Yue1 and Yunling Liu1

+ Author Affiliations

 Corresponding author: Wang Shengli, wsl619@126.com; Wang Shengli, wsl619@126.com

PDF

Abstract: The planarization mechanism of alkaline copper slurry is studied in the chemical mechanical polishing (CMP) process from the perspective of chemical mechanical kinetics. Different from the international dominant acidic copper slurry, the copper slurry used in this research adopted the way of alkaline technology based on complexation. According to the passivation property of copper in alkaline conditions, the protection of copper film at the concave position on a copper pattern wafer surface can be achieved without the corrosion inhibitors such as benzotriazole (BTA), by which the problems caused by BTA can be avoided. Through the experiments and theories research, the chemical mechanical kinetics theory of copper removal in alkaline CMP conditions was proposed. Based on the chemical mechanical kinetics theory, the planarization mechanism of alkaline copper slurry was established. In alkaline CMP conditions, the complexation reaction between chelating agent and copper ions needs to break through the reaction barrier. The kinetic energy at the concave position should be lower than the complexation reaction barrier, which is the key to achieve planarization.

Key words: chemical mechanical kineticsalkaline copper slurryplanarization mechanismcomplexationreaction barrier



[1]
Hu Y, Liu Y L, Liu X Y, et al. Effect of alkaline slurry on the electric character of the pattern Cu wafer. Journal of Semiconductors, 2011, 32(7):076002 doi: 10.1088/1674-4926/32/7/076002
[2]
Ruan W B, Chen L, Li Z G, et al. Effects of pattern characteristics on copper CMP. Journal of Semiconductors, 2009, 30(4):046001 doi: 10.1088/1674-4926/30/4/046001
[3]
Li X, Liu Y L, Wang C W, et al. Study of the stability of H2O2 in alkaline slurry. Adv Semicond Manuf Technol, 2012, 37(11):850
[4]
Yin K D, Wang S L, Liu Y L, et al. Impact of the temperature and mass transfer on the removal rate uniformity in copper CMP process. Adv Semicond Manuf Technol, 2012, 37(10):768
[5]
Fayolle M, Romagna F. Copper CMP evaluation:planarization issues. Microelectron Eng, 1997, 37/38:135 doi: 10.1016/S0167-9317(97)00104-4
[6]
Pandija S, Roy D, Babu S V. Chemical mechanical planarization of copper using abrasive-free solutions of oxalic acid and hydro-gen peroxide. Mater Chem Phys, 2007, 102(2/3):144
[7]
Price D T, Gutmann R J, Murarka S P. Damascene copper interconnects with polymer ILDs. Thin Solid Films, 1997, 308/309:523
[8]
Kriz J, Angelkort C, Czekalla M, et al. Overview of dual damascene integration schemes in Cu BEOL integration. Microelectron Eng, 2008, 85(10):2128 doi: 10.1016/j.mee.2008.05.034
[9]
Su J X, Du J X, Ma L J, et al. Material removal rate of 6H-SiC crystal substrate CMP using an alumina (Al2O3) abrasive. Journal of Semiconductors, 2012, 33(10):106003 doi: 10.1088/1674-4926/33/10/106003
[10]
Wang C W, Liu Y L, Niu X H, et al. An advanced alkaline slurry for barrier chemical mechanical planarization on patterned wafers. Journal of Semiconductors, 2012, 33(4):046001 doi: 10.1088/1674-4926/33/4/046001
[11]
Wang C W, Liu Y L, Tian J Y, et al. Planarization properties of an alkaline slurry without an inhibitor on copper patterned wafer CMP. Journal of Semiconductors, 2012, 33(11):116001 doi: 10.1088/1674-4926/33/11/116001
Fig. 1.  Structure of 300 mm copper pattern wafer. (a) Cross sectional view. (b) Step height test position.

Fig. 2.  Step height on copper pattern wafer surface pre-CMP.

Fig. 3.  Dissolution rate versus polishing rate.

Fig. 4.  Planarization schematic diagram.

Fig. 5.  Relationship between step height and H$_{2}$O$_{2}$ concentration post-CMP.

Fig. 6.  Effect of pressure on the planarization.

[1]
Hu Y, Liu Y L, Liu X Y, et al. Effect of alkaline slurry on the electric character of the pattern Cu wafer. Journal of Semiconductors, 2011, 32(7):076002 doi: 10.1088/1674-4926/32/7/076002
[2]
Ruan W B, Chen L, Li Z G, et al. Effects of pattern characteristics on copper CMP. Journal of Semiconductors, 2009, 30(4):046001 doi: 10.1088/1674-4926/30/4/046001
[3]
Li X, Liu Y L, Wang C W, et al. Study of the stability of H2O2 in alkaline slurry. Adv Semicond Manuf Technol, 2012, 37(11):850
[4]
Yin K D, Wang S L, Liu Y L, et al. Impact of the temperature and mass transfer on the removal rate uniformity in copper CMP process. Adv Semicond Manuf Technol, 2012, 37(10):768
[5]
Fayolle M, Romagna F. Copper CMP evaluation:planarization issues. Microelectron Eng, 1997, 37/38:135 doi: 10.1016/S0167-9317(97)00104-4
[6]
Pandija S, Roy D, Babu S V. Chemical mechanical planarization of copper using abrasive-free solutions of oxalic acid and hydro-gen peroxide. Mater Chem Phys, 2007, 102(2/3):144
[7]
Price D T, Gutmann R J, Murarka S P. Damascene copper interconnects with polymer ILDs. Thin Solid Films, 1997, 308/309:523
[8]
Kriz J, Angelkort C, Czekalla M, et al. Overview of dual damascene integration schemes in Cu BEOL integration. Microelectron Eng, 2008, 85(10):2128 doi: 10.1016/j.mee.2008.05.034
[9]
Su J X, Du J X, Ma L J, et al. Material removal rate of 6H-SiC crystal substrate CMP using an alumina (Al2O3) abrasive. Journal of Semiconductors, 2012, 33(10):106003 doi: 10.1088/1674-4926/33/10/106003
[10]
Wang C W, Liu Y L, Niu X H, et al. An advanced alkaline slurry for barrier chemical mechanical planarization on patterned wafers. Journal of Semiconductors, 2012, 33(4):046001 doi: 10.1088/1674-4926/33/4/046001
[11]
Wang C W, Liu Y L, Tian J Y, et al. Planarization properties of an alkaline slurry without an inhibitor on copper patterned wafer CMP. Journal of Semiconductors, 2012, 33(11):116001 doi: 10.1088/1674-4926/33/11/116001
  • Search

    Advanced Search >>

    GET CITATION

    shu

    Export: BibTex EndNote

    Article Metrics

    Article views: 2225 Times PDF downloads: 12 Times Cited by: 0 Times

    History

    Received: 16 December 2012 Revised: 11 January 2013 Online: Published: 01 August 2013

    Catalog

      Email This Article

      User name:
      Email:*请输入正确邮箱
      Code:*验证码错误
      Shengli Wang, Kangda Yin, Xiang Li, Hongwei Yue, Yunling Liu. Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics[J]. Journal of Semiconductors, 2013, 34(8): 086003. doi: 10.1088/1674-4926/34/8/086003 S L Wang, K D Yin, X Li, H W Yue, Y L Liu. Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics[J]. J. Semicond., 2013, 34(8): 086003. doi: 10.1088/1674-4926/34/8/086003.Export: BibTex EndNote
      Citation:
      Shengli Wang, Kangda Yin, Xiang Li, Hongwei Yue, Yunling Liu. Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics[J]. Journal of Semiconductors, 2013, 34(8): 086003. doi: 10.1088/1674-4926/34/8/086003

      S L Wang, K D Yin, X Li, H W Yue, Y L Liu. Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics[J]. J. Semicond., 2013, 34(8): 086003. doi: 10.1088/1674-4926/34/8/086003.
      Export: BibTex EndNote

      Planarization mechanism of alkaline copper CMP slurry based on chemical mechanical kinetics

      doi: 10.1088/1674-4926/34/8/086003
      Funds:

      Project supported by the Special Project Items No. 2 in National Long-term Technology Development Plan, China (No. 2009ZX02308)

      the Special Project Items No. 2 in National Long-term Technology Development Plan, China 2009ZX02308

      More Information
      • Corresponding author: Wang Shengli, wsl619@126.com; Wang Shengli, wsl619@126.com
      • Received Date: 2012-12-16
      • Revised Date: 2013-01-11
      • Published Date: 2013-08-01

      Catalog

        /

        DownLoad:  Full-Size Img  PowerPoint
        Return
        Return