SEMICONDUCTOR TECHNOLOGY

A novel compound cleaning solution for benzotriazole removal after copper CMP

Zhangbing Gu, Yuling Liu, Baohong Gao, Chenwei Wang and Haiwen Deng

+ Author Affiliations

PDF

Abstract: After the chemical mechanical planarization (CMP) process, the copper surface is contaminated by a mass of particles (e.g.silica) and organic residues (e.g.benzotriazole), which could do great harm to the integrated circuit, so post-CMP cleaning is essential.In particular, benzotriazole (BTA) forms a layer of Cu-BTA film with copper on the surface, which leads to a hydrophobic surface of copper.So an effective cleaning solution is needed to remove BTA from the copper surface.In this work, a new compound cleaning solution is designed to solve two major problems caused by BTA:one is removing BTA and the other is copper surface corrosion that is caused by the cleaning solution.The cleaning solution is formed of alkaline chelating agent (FA/O II type), which is used to remove BTA, and a surfactant (FA/O I type), which is used as a corrosion inhibitor.BTA removal is characterized by contact angle measurements and electrochemical techniques.The inhibiting corrosion ability of the surfactant is also characterized by electrochemical techniques.The proposed compound cleaning solution shows advantages in removing BTA without corroding the copper surface.

Key words: benzotriazole removalalkaline chelating agentsurfactantcorrosion inhibitor



[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
Fig. 1.  Structure diagram of FA/O II chelating agent.

Fig. 2.  Corrosion potential of the copper electrode in the mixed electrolyte of chelating agent and surfactant.

Fig. 3.  Contact angle of deionized water on Cu surface dipped in BTA solution of 10 mM and cleaned with DIW and various solutions given in Table 1

Fig. 4.  Contact angle of de-ionized water on Cu surface cleaned with various solutions.

Fig. 5.  (Color online) The Tafel curves of Cu in a solution containing only electrolyte of 4.25 g/L NaNO$_{3}$.

Fig. 6.  AFM images of the copper coupons.

Fig. 7.  Schematic of BTA and Cu-BTA removal.

Table 1.   Cleaning solutions with different ratios to remove BTA.

Cleaning solutionFA/O II chelating agent (ppm)FA/O I surfactant (ppm)
A50100
B100100
C150400
D200400
E250600
DownLoad: CSV

Table 2.   The corrosion potential and the corresponding corrosion current density.

Solutions$E_{\rm corr}$ (V) versus $E_{\rm SCE}$$I_{\rm corr}$ ($\mu$A/cm$^{2})$
DIW$-0.144$0.166
A$-0.232$3.193
B$-0.255$4.166
C$-0.280$6.582
D$-0.336$8.493
E$-0.342$8.670
DownLoad: CSV
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
[9]
[10]
[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[19]
[20]
[21]
[22]
  • Search

    Advanced Search >>

    GET CITATION

    shu

    Export: BibTex EndNote

    Article Metrics

    Article views: 3458 Times PDF downloads: 56 Times Cited by: 0 Times

    History

    Received: 08 April 2015 Revised: Online: Published: 01 October 2015

    Catalog

      Email This Article

      User name:
      Email:*请输入正确邮箱
      Code:*验证码错误
      Zhangbing Gu, Yuling Liu, Baohong Gao, Chenwei Wang, Haiwen Deng. A novel compound cleaning solution for benzotriazole removal after copper CMP[J]. Journal of Semiconductors, 2015, 36(10): 106001. doi: 10.1088/1674-4926/36/10/106001 Z B Gu, Y L Liu, B H Gao, C W Wang, H W Deng. A novel compound cleaning solution for benzotriazole removal after copper CMP[J]. J. Semicond., 2015, 36(10): 106001. doi: 10.1088/1674-4926/36/10/106001.Export: BibTex EndNote
      Citation:
      Zhangbing Gu, Yuling Liu, Baohong Gao, Chenwei Wang, Haiwen Deng. A novel compound cleaning solution for benzotriazole removal after copper CMP[J]. Journal of Semiconductors, 2015, 36(10): 106001. doi: 10.1088/1674-4926/36/10/106001

      Z B Gu, Y L Liu, B H Gao, C W Wang, H W Deng. A novel compound cleaning solution for benzotriazole removal after copper CMP[J]. J. Semicond., 2015, 36(10): 106001. doi: 10.1088/1674-4926/36/10/106001.
      Export: BibTex EndNote

      A novel compound cleaning solution for benzotriazole removal after copper CMP

      doi: 10.1088/1674-4926/36/10/106001
      Funds:

      Project supported by the Special Project Items No.2 in National Long-Term Technology Development Plan, China (Nos.2009ZX02308-003, 2014ZX02301003-007).

      • Received Date: 2015-04-08
      • Accepted Date: 2015-05-21
      • Published Date: 2015-01-25

      Catalog

        /

        DownLoad:  Full-Size Img  PowerPoint
        Return
        Return