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Article

Effects of CTAB (Cetyltrimethylammonium Bromide) and Betaine as Corrosion Inhibitors on the Galvanic Corrosion of Cu Coupled with Au on Print Circuit Board in Etching Solution

by
HeeKwon Shin
and
SeKwon Oh
*
Industrial Components R&D Department, Korea Institute of Industrial Technology, Incheon 21999, Republic of Korea
*
Author to whom correspondence should be addressed.
Metals 2024, 14(9), 1090; https://doi.org/10.3390/met14091090
Submission received: 9 August 2024 / Revised: 19 September 2024 / Accepted: 20 September 2024 / Published: 23 September 2024
(This article belongs to the Special Issue Advances in Corrosion and Protection of Materials (Second Edition))
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Abstract

:
This study investigates the suppression of galvanic corrosion between copper and gold using cetyltrimethylammonium bromide (CTAB) and betaine as inhibitors. When copper is electrically connected to gold in PCB etching solutions, the substantial difference in their electrochemical potentials leads to the accelerated corrosion of copper, posing severe reliability risks. To mitigate this, we systematically investigated the galvanic corrosion inhibition properties of CTAB and betaine. Through comprehensive electrochemical analyses, it was found that the galvanic corrosion current density of copper, initially at 3.26 mA/cm2, decreased significantly to 0.251 mA/cm2 with 0.9 mM CTAB, indicating an inhibition efficiency of 92.3%. Furthermore, betaine, at a concentration of 0.1 mM, demonstrated an even higher inhibition efficiency, reducing the corrosion current to 0.03 mA/cm2, achieving a 99.1% inhibition rate. These findings provide strong evidence that CTAB and betaine are highly effective in suppressing galvanic corrosion in copper–gold systems, thereby enhancing the long-term performance and reliability of PCBs in electronic applications.

1. Introduction

Copper is extensively used in industries such as electronics, construction, cooling systems, and alloys due to its malleability and ductility [1,2]. Its high electrical and thermal conductivity make it particularly suited for use in wires and pads for electrical connections in printed circuit boards (PCBs). PCBs typically consist of copper circuits and pads, with gold pads applied to enhance adhesion between the solder ball and copper pad [3,4,5]. The substrate of PCBs generally undergoes etching in acidic solutions to remove contaminants and improve the surface roughness of the metal pads. While etching is typically designed for uncoupled copper, during the process, electrically coupled copper–gold systems can experience over-etching, leading to reliability concerns. This occurs due to the significant electrochemical potential difference between copper (E°Cu2⁺/Cu = +0.34 V) and gold (E°Au⁺/Au = +1.7 V), which results in galvanic corrosion. Copper, being the more active metal, corrodes more rapidly when in contact with gold in the same electrolyte solution [6,7]. The over-etching of copper is caused by this galvanic corrosion, driven by the potential difference between copper (E°Cu2⁺/Cu = +0.34 V) and gold (E°Au⁺/Au = +1.7 V). When two dissimilar metals are placed in the same electrolyte, galvanic corrosion occurs on the metal with more active electrical potential, accelerating copper corrosion [8,9,10]. To mitigate galvanic corrosion, numerous corrosion inhibitors have been explored. These inhibitors form protective films by adsorbing onto the metal surface [11,12,13,14,15,16,17,18,19,20,21,22]. Hualiang Huang [23] evaluated copper corrosion inhibition in a NaCl solution using benzimidazole (BI), 2-mercaptobenzimidazole (MBI), and benzotriazole (BTA), with BTA showing the highest inhibition efficiency. Similarly, Shenghua [24] utilized 1-phenyl-3-methyl-5-pyrazolone (PMP) and BTA to inhibit galvanic corrosion between copper and cobalt in H2O2 solutions, achieving a significant reduction in corrosion. The combination of PMP and BTA strongly mitigated galvanic corrosion. Caroline M. Murira [25] reported that CTAB effectively inhibited the galvanic corrosion of copper coupled with gold in a microreactor system, suppressing the corrosion by 99.5% by inhibiting the cathodic reaction on the gold surface. Additionally, Houyi Ma [26] demonstrated that CTAB inhibits copper corrosion in aerated H2SO4 solutions via the chemisorption of the n-cetyl group onto the copper surface. The inhibition efficiency varied depending on CTAB concentration and immersion time. Ma proposed an adsorption model, where horizontal binding occurs at low concentrations, transitioning to perpendicular adsorption at higher concentrations. M. El Bakri [27] studied the effects of triazole (TR), 3-amino-1,2,4-triazole (ATA), and CTAB on brass corrosion in a simulated cooling water system using electrochemical methods, SEM, and EDX analysis. ATA proved to be the most effective inhibitor, with improved inhibition efficiency under conditions of increased pH, immersion time, and temperature. The study revealed mixed-type inhibition, dependent on the nitrogen content in the inhibitor’s structure. Chaodang Wu [28] investigated the effects of sodium lauryl ether sulfate and betaine as corrosion inhibitors on carbon steel in a NaCl solution, reporting inhibition efficiencies of 82% and 78%, respectively. While studies on corrosion inhibitors such as CTAB and betaine for various metals have been conducted [25,26,27,28,29], research specifically focusing on the galvanic corrosion inhibition of copper coupled with gold in PCB etching solutions remains limited.
In this study, we investigate the effects of CTAB and betaine as corrosion inhibitors on the galvanic corrosion of copper coupled with gold in PCB etching solutions through electrochemical experiments. Additionally, we explore the inhibition mechanisms of these inhibitors on the galvanic corrosion of copper in copper–gold systems.

2. Experimental

For the copper specimen, a copper foil on a copper-clad laminate (CCL) was used to simulate an actual printed circuit board system, and the exposed working area of the copper specimen was 0.2826 cm2 (diameter 0.5 cm, circular shape).
For the gold specimen, to prevent the formation of an intermetallic compound between copper and gold, nickel was electroplated onto the copper substrate. Nickel electrodeposition was conducted for 15 min at 40 °C using a cathodic current density of 100 mA/cm2 from a solution containing 0.45 M NiSO4·6H2O, 0.126 M NiCl2·6H2O, and 0.8 M H3BO3. Then, gold was electroplated onto the nickel substrate for 10 min and 30 s at 50 °C using a cathodic current density of 1.5 mA/cm2 from a solution containing 50 mM KAu(CN)2. The exposed working area of the gold specimen was 0.2826 cm2 (diameter 0.5 cm, circular shape), with the exposed area ratio of copper to gold being 1:1. The PCB etching solution was prepared by mixing 0.28 M H2SO4, 0.42 M H2O2, 0.28 M CuCl2·2H2O, and deionized water. The pH of the etching solution was 0.47. These were directly added to the etching solution at varying concentrations. Electrochemical experiments were performed at an ambient temperature of 25 ± 1 °C using a Versastat4 electrochemical workstation (Ametek). To investigate the corrosion behavior of copper and gold, a potentiodynamic polarization test was performed using a conventional three-electrode system, with the test specimens (Cu, Au) serving as the working electrode (WE), Pt as the counter electrode (CE), and a saturated calomel electrode (SCE) as the reference electrode (RE) [30]. The open circuit potential (OCP) of the working electrode was measured until it stabilized sufficiently in the solution for 30 min, after which polarization testing was conducted. Once the OCP stabilized, the polarization test was performed with a scan rate of 1 mV/s, with a scan potential range from −200 mV to +400 mV relative to the OCP. To study the galvanic current density (icouple) between the copper and gold electrodes in the etching solution, a galvanic corrosion test (zero resistance ammeter test) was conducted using a two-electrode system. The copper specimen was used as the working electrode (WE), and the gold specimen as both the counter electrode (CE) and the reference electrode (RE). The galvanic corrosion test was conducted according to the type and concentration of the corrosion inhibitor, lasting for 600 s.

3. Results and Discussion

Figure 1a illustrates the polarization curves of copper and gold to assess their corrosion behavior in the PCB etching solution. When the polarization curve test was conducted in the PCB etching solution, the corrosion potential of copper was −7.01 mVSCE, and the corrosion rate was determined to be 0.49 mA/cm2. The polarization behavior of gold in the PCB etching solution is also indicated as a red line in Figure 2.
The Ecorr and icorr were 91 mVSCE and 0.09 mA/cm2, respectively. The polarization curve test showed a significant difference in corrosion potential between gold and copper. When these two metals are electrically connected, copper assumes the role of the anode, while gold takes on the role of the cathode, leading to an acceleration in copper corrosion due to galvanic corrosion, primarily because of copper’s lower corrosion potential. Figure 1b represents the results of the zero-resistance ammeter (ZRA) test conducted on electrically connected copper and gold in the PCB etching solution. The ZRA test revealed that galvanic corrosion occurs due to the difference in corrosion potential between copper and gold in the PCB etching solution. During this process, the galvanic corrosion current (icouple, (Cu-Au)) flowing between copper and gold was measured at 3.26 mA/cm2. Comparing this with the corrosion current of isolated copper measured through the polarization curve test (icorr, Cu) at 0.49 mA/cm2, it was found that the galvanic corrosion current increased by 6.6 times. This confirms that in the presence of an electrical connection between copper and gold in the PCB etching solution, the corrosion rate of copper coupled with gold increases 6.6 times compared with single copper. Figure 2a–c shows the surface morphology of single copper and copper coupled with gold before and after PCB etching. Figure 2a presents the surface morphology of copper before etching, revealing a smooth surface morphology. Figure 2b illustrates the surface morphology of single copper and electrically connected copper to Au (Figure 2c) after etching in the PCB solution. The specimen connected to gold exhibits a rougher surface due to the galvanic corrosion phenomenon. Figure 3a–c reveals the surface morphology measured using atomic force microscopy (AFM).
The surface roughness of copper before etching measures 0.499 µm. When treated with the etching solution, the surface roughness of a single copper is measured at 0.527 µm, while electrically connected copper exhibits a surface roughness of 0.538 µm. This confirms that galvanic corrosion accelerates copper corrosion when it is electrically connected to gold. Figure 4 and Table 1 illustrate the results of ZRA tests conducted to assess the galvanic corrosion inhibition effect of CTAB when copper and gold are electrically connected in the PCB etching solution.
Different concentrations of CTAB, specifically 0.6 mM, 0.9 mM, and 1.2 mM, were introduced into the PCB etching solution. Subsequently, ZRA tests were carried out to measure the galvanic corrosion current, and the galvanic corrosion inhibition effect (IE) for each concentration was compared. Previously, the galvanic corrosion current of Cu coupled with gold in the PCB etching solution was 3.26 mA/cm2. However, when 0.6 mM CTAB was introduced, the corrosion current decreased to 0.453 mA/cm2, resulting in an 86.1% corrosion inhibition effect compared with the results without the corrosion inhibitor. At 0.9 mM CTAB, the current decreased further to 0.251 mA/cm2, yielding a 92.3% inhibition effect. In the case of 1.2 mM CTAB, the corrosion current measured at 0.474 mA/cm2, signifying an 85.5% corrosion inhibition effect. The results of comparing the galvanic corrosion inhibition effect of copper with varying CTAB concentrations revealed that the IE value increased up to 0.9 mM CTAB concentration, indicating an increasing corrosion inhibition effect. Indeed, when the CTAB concentration surpasses 0.9 mM, there is a noticeable reduction in the IE value. This behavior is attributed to the nature of CTAB as a surfactant with amphiphilic character. CTAB effectively inhibits copper corrosion with a hydrophobic tail binding to the metal surface and a hydrophilic head exposed to the solution. This results in the formation of a thin protective film on the metal surface, which prevents direct contact between the metal surface and the corrosive environment, thereby inhibiting the corrosion reaction. At lower concentrations (~0.6 mM), CTAB adsorbs onto metal through a combination of chemisorption of the n-cetyl chain and electrostatic interactions between the C16H33N(CH3)3+ ions and pre-adsorbed bromide ions on the metal surface. This creates a protective layer that minimizes corrosion by preventing direct contact with the corrosive medium [26]. The concentration at which a surfactant begins to form micelles and its corrosion inhibition effect diminishes is known as the critical micelle concentration (CMC). At this concentration, the adsorption behavior shifts as the hydrophobic chains of CTAB molecules interact through van der Waals forces, creating a compact and densely packed barrier that enhances the corrosion inhibition effect. However, as CTAB concentrations exceed 0.9 mM, excessive surface coverage can slightly decrease the inhibition efficiency due to changes in adsorption dynamics, as more molecules are adsorbed, but the effective surface area covered may be reduced. To compare the galvanic corrosion inhibition effects at different betaine concentrations, ZRA tests were conducted using concentrations of 0.05 mM, 0.1 mM, and 0.2 mM, as shown in Figure 5 and Table 2.
In the PCB etching solution, the ZRA test results showed that at a betaine concentration of 0.05 mM, the galvanic corrosion current measured 0.14 mA/cm2. This represents a 95.7% reduction in galvanic corrosion current compared with the solution without the corrosion inhibitor. When the betaine concentration was increased to 0.1 mM, the galvanic corrosion current dropped to 0.03 mA/cm2, demonstrating a corrosion inhibition efficiency of 99.1%. However, at 0.2 mM betaine, the galvanic corrosion current increased slightly to 0.146 mA/cm2, resulting in a 95.5% inhibition effect. The comparison of corrosion inhibition effects based on betaine concentration revealed an increase in the IE value up to a concentration of 0.1 mM, indicating an escalating corrosion inhibition effect. However, at concentrations exceeding 0.1 mM, a decrease in the IE value was observed as betaine concentration increased. This phenomenon is attributed to the CMC of betaine, which is 0.1 mM. The hydrophilic head of betaine with polar properties adsorbs to the copper surface and effectively inhibits copper corrosion until the betaine concentration reaches 0.1 mM. However, exceeding concentrations of 0.1 mM, betaine forms micellar structures, leading to a reduction in its corrosion inhibition effect. Figure 6 illustrates the results of the potentiodynamic polarization test, which was conducted to evaluate the effect of CTAB on the corrosion behavior of copper and gold in the PCB etching solution at 25 °C. The test was conducted by adding the most effective concentration of CTAB, which was determined through ZRA testing to be 0.9 mM.
The changes in corrosion potential (Ecorr) and corrosion current density (icorr) were confirmed during this test. The addition of CTAB in the solution significantly decreases both the anodic and cathodic current density of copper; although, the corrosion potential was shifted negatively. The addition of CTAB resulted in a significant decrease in the corrosion potential of copper, from −7.01 mV to −84 mV, and a substantial reduction in the corrosion current density, from 0.49 mA to 0.0281 mA/cm2 (Table 3).
The calculated corrosion inhibition effect of CTAB showed a reduction of approximately 94% compared with the solution without the inhibitor. For Au with the addition of CTAB, the corrosion potential value decreased to −172 mV, However, the corrosion current actually increased from 0.007 to 0.386 mA/cm2. The CTAB, a cationic surfactant, has a negatively charged head group. It adsorbs well onto the copper surface in the etching solution, inhibiting the corrosion rate. However, it does not affect the corrosion rate of gold due to poor adsorption. This confirms that CTAB adsorbs to the copper surface rather than Au in the PCB etching solution, leading to a corrosion inhibition effect and a significant decrease in corrosion rate. To investigate the influence of betaine as a corrosion inhibitor on the corrosion inhibition of copper and gold, a potentiodynamic polarization test was conducted in a solution containing 0.1 mM betaine (Figure 7).
The potentiodynamic polarization test results for copper exhibited negligible variation in the corrosion potential (Ecorr), which consistently fell within the range of −7.01 mV to −12 mV. However, the corrosion current of copper significantly decreased from 0.49 mA/cm2 to 0.0051 mA/cm2 with the addition of betaine, demonstrating a substantial decrease in corrosion current by the addition of betaine, as shown in Table 3. The potentiodynamic polarization test results for gold specimens revealed that the addition of betaine led to a decrease in the corrosion potential, reducing it from 91 mV to 42 mV. Additionally, the corrosion current of gold specimens decreased from 0.09 mA/cm2 to 0.007 mA/cm2 with the addition of betaine. These observations confirm that betaine not only adsorbs onto copper specimens, reducing their corrosion rate, but also exhibits a similar protective effect on gold specimens, effectively slowing down their corrosion rate. Betaine (BTA), as a zwitterionic surfactant with both positive and negative charges in its head group, inhibits the corrosion of both copper and gold by adsorbing onto both surfaces, unlike CTAB, which selectively adsorbs only onto copper. Comparing the galvanic corrosion evaluation results in Figure 5 and Figure 6, the galvanic corrosion inhibition effect of betaine was 99.1%, and CTAB had a relatively high galvanic corrosion inhibition rate of 92.3%. These results suggest that betaine, functioning as an amphoteric surfactant, effectively adsorbs onto both copper and gold surfaces, thereby reducing the galvanic corrosion rate.

4. Conclusions

In this study, the inhibiting effects of CTAB and betaine as corrosion inhibitors on the galvanic corrosion of Cu coupled with gold in a PCB etching solution were investigated using electrochemical techniques. The polarization test results demonstrated that copper acts as the anode with a corrosion potential of −7.01 mVSCE, while gold functions as the cathode with a corrosion potential of 91 mVSCE. The substantial difference in corrosion potentials between copper and gold facilitates galvanic corrosion in the etching solution, leading to the accelerated corrosion of copper when the metals are electrically connected. Both CTAB and betaine were evaluated for their effectiveness as corrosion inhibitors. CTAB, at an optimal concentration of 0.9 mM, reduced the galvanic corrosion current density from 3.26 mA/cm2 to 0.251 mA/cm2, corresponding to a corrosion inhibition efficiency of approximately 92.3%. In comparison, betaine showed superior performance as a corrosion inhibitor, with concentrations up to 0.1 mM reducing the corrosion current to 0.03 mA/cm2, corresponding to an inhibition efficiency of approximately 99.1%. The differences in inhibition effectiveness are attributed to the interaction of the surfactants with the metal surfaces. CTAB adsorbs preferentially on copper surfaces, effectively reducing corrosion rates by inhibiting anodic processes, whereas betaine exhibits adsorption on both copper and gold surfaces, mitigating galvanic corrosion by blocking both anodic and cathodic reactions. These findings enhance the understanding of surfactants’ roles in mitigating galvanic corrosion in PCB manufacturing processes, demonstrating that CTAB and betaine are effective inhibitors under specific conditions.

Author Contributions

Conceptualization, S.O.; methodology, S.O.; software, H.S.; formal analysis, H.S.; investigation, H.S.; resources, S.O.; data curation, H.S.; writing—original draft preparation, S.O.; writing—review and editing, S.O.; visualization, H.S.; supervision, S.O.; project administration, S.O.; funding acquisition, S.O. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the Ministry of Trade, Industry and Energy (MOTIE) of Republic of Korea (No. 20019192).

Data Availability Statement

The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Miura, S.; Honma, H. Advanced copper electroplating for application of electronics. Surf. Coat. Technol. 2003, 169, 91. [Google Scholar] [CrossRef]
  2. Li, Z.; Chang, S.; Khuje, S.; Ren, S. Recent Advancement of Emerging Nano Copper-Based Printable Flexible Hybrid Electronics. ACS Nano 2021, 15, 6211. [Google Scholar] [CrossRef] [PubMed]
  3. Julian, Y.; Hon, C.; Cotterell, B.; Chai, T.C. The mechanics of the solder ball shear test and the effect of shear rate. Mater. Sci. Eng. A 2006, 417, 259. [Google Scholar]
  4. Wang, J.; Lim, H.K.; Lew, H.S.; Saw, W.T.; Tan, C.H. A testing method for assessing solder joint reliability of FCBGA packages. Microelectron. Reliab. 2004, 44, 833. [Google Scholar] [CrossRef]
  5. Doranga, S.; Schuldt, M.; Khanal, M. Effect of Stiffening the Printed Circuit Board in the Fatigue Life of the Solder Joint. Materials 2022, 15, 6208. [Google Scholar] [CrossRef]
  6. Murira, M.C.; Punckt, C.; Schniepp, H.C.; Khusid, B.; Aksay, I.A. Inhibition and Promotion of Copper Corrosion by CTAB in a Microreactor System. Langmuir 2008, 24, 14269. [Google Scholar] [CrossRef]
  7. Oh, S.; Kim, Y.; Jung, K.; Kim, J.; Shon, M.; Kwon, H. Effects of Temperature and Operation Parameters on the Galvanic Corrosion of Cu Coupled to Au in Organic Solderability Preservatives Process. Met. Mater. Int. 2017, 23, 290. [Google Scholar] [CrossRef]
  8. Xiao-qing, D.; Yang, Q.; Chen, Y.; Yang, Y.; Zhao, Z. Galvanic corrosion behavior of copper/titanium galvanic couple in artificial seawater. Trans. Nonferrous Met. Soc. China 2014, 24, 570. [Google Scholar]
  9. Idrac, J.; Mankowski, G.; Thompson, G.; Skeldon, P.; Kihn, Y.; Blan, C. Galvanic corrosion of aluminium–copper model alloys. Electrochim. Acta 2007, 52, 7626. [Google Scholar] [CrossRef]
  10. Huh, M.; Yu, Y.; Kahn, H.; Payer, J.H.; Heuer, A.H. Galvanic Corrosion during Processing of Polysilicon Microelectromechanical Systems. J. Electrochem. Soc. 2006, 153, 644. [Google Scholar] [CrossRef]
  11. Oh, S.; Kim, Y.; Shon, M.; Kwon, H. Galvanic Corrosion of Cu Coupled to Au on a Printed Circuit Board; Effects of Pretreatment Solution and Etchant Concentration in Organic Solderability Preservatives Soft Etching Solution. Met. Mater. Int. 2016, 22, 781. [Google Scholar] [CrossRef]
  12. Huang, H.; Guo, X.; Zhang, G.; Dong, Z. The effects of temperature and electric field on atmospheric corrosion behaviour of PCB-Cu under absorbed thin electrolyte layer. Corros. Sci. 2011, 53, 1700. [Google Scholar] [CrossRef]
  13. Oh, S.; Kim, Y.; Jung, K.; Park, M.; Shon, M.; Kwon, H. Galvanic Corrosion Behaviors of Cu Connected to Au on a Printed Circuit Board in Ammonia Solution. Met. Mater. Int. 2018, 24, 67. [Google Scholar] [CrossRef]
  14. Khadom, A.A.; Abod, B.M.; Mahood, H.B.; Kadhum, A.A.H. Galvanic Corrosion of Steel–Brass Couple in Petroleum Waste Water in Presence of a Green Corrosion Inhibitor: Electrochemical, Kinetics, and Mathematical View. J. Fail. Anal. Preven. 2018, 18, 1300–1310. [Google Scholar] [CrossRef]
  15. Wang, X.; Liu, S.; Yan, J.; Zhang, J.; Zhang, Q.; Yan, Y. Recent Progress of Polymeric Corrosion Inhibitors: Structure and Application. Materials 2023, 16, 2954. [Google Scholar] [CrossRef]
  16. Samarawickrama, C.; Pöhlker, S.; White, P.; Cole, I.; Keil, P. Corrosion Inhibitor Screening for AA6014 Aluminum Alloy Under Different Ambient Conditions Using a Novel Multielectrode Methodology. Mol. Syst. Des. Eng. 2024, 9, 518–531. [Google Scholar] [CrossRef]
  17. Kamburova, K.; Boshkova, N.; Radeva, T.; Shipochka, M.; Boshkov, N. Chitosan–Alginate Nanocontainers with Caffeine as Green Corrosion Inhibitors for Protection of Galvanized Steel. Crystals 2024, 14, 660. [Google Scholar] [CrossRef]
  18. Shwetha, K.M.; Praveen, B.M.; Devendra, B.K. A Review on Corrosion Inhibitors: Types, Mechanisms, Electrochemical Analysis, Corrosion Rate and Efficiency of Corrosion Inhibitors on Mild Steel in an Acidic Environment. Results Surf. Interfaces 2024, 16, 100258–100277. [Google Scholar]
  19. Wulandari, M.; Nofrizal, N.; Impey, S.; Georgarakis, K.; Raja, P.B.; Hussin, M.H. The Effect of Corrosion Inhibitor on X-65 Steel Weldment in High Flow Rate Conditions. Case Stud. Chem. Environ. Eng. 2024, 10, 100868–100876. [Google Scholar] [CrossRef]
  20. Hussein, S.A.; Khadom, A.A. Okra Leaves Extract as Green Corrosion Inhibitor for Steel in Sulfuric Acid: Gravimetric, Electrochemical, and Surface Morphological Investigations. Results Chem. 2024, 8, 101566–101577. [Google Scholar] [CrossRef]
  21. Farh, H.M.H.; Ben Seghier, M.E.A.; Zayed, T. A Comprehensive Review of Corrosion Protection and Control Techniques for Metallic Pipelines. Eng. Fail. Anal. 2023, 143, 106885–106907. [Google Scholar] [CrossRef]
  22. Xu, Z.; Cao, X.; Wang, P.; Jiang, J.; Zhang, H.; Slaný, M.; Bian, J. Shielding against Erosion: Exploring the Effectiveness of Pre-Erosion Surface Corrosion Inhibitors. J. Colloid. Interface Sci. 2024, 675, 1130–1148. [Google Scholar] [CrossRef] [PubMed]
  23. Huang, H.; Bu, F. Correlations between the inhibition performances and the inhibitor structures of some azoles on the galvanic corrosion of copper coupled with silver in artificial seawater. Corros. Sci. 2020, 165, 108413. [Google Scholar] [CrossRef]
  24. Yang, S.; Zhang, B.; Zhang, Q.; Wang, R.; Yu, X.; Wang, C.; Liu, Y. A Study of Cobalt Galvanic and Pitting Corrosion with combination of BTA and PMP. ECS J. Solid State Sci. Technol. 2019, 8, 416. [Google Scholar] [CrossRef]
  25. Sargolzaei, B.; Arab, A. Synergism of CTAB and NLS surfactants on the corrosion inhibition of mild steel in sodium chloride solution. Mater. Today Commun. 2021, 29, 102809. [Google Scholar] [CrossRef]
  26. Ma, H.; Chen, S.; Zhao, S.; Liu, X.; Li, D. A Study of Corrosion Behavior of Copper in Acidic Solutions Containing Cetyltrimethylammonium Bromide. J. Electrochem. Soc. 2001, 148, 482–488. [Google Scholar] [CrossRef]
  27. El Bakri, M.; Touir, R.; Tazouti, A.; Dkhireche, N.; Ebn Touhami, M.; Rochdi, A.; Zarrouk, A. Corrosion Inhibition Study of Brass in Simulated Cooling Water by Triazole Derivatives, Cetyltrimethylammonium Bromide and Their Mixture. Arab. J. Sci. Eng. 2016, 41, 75–88. [Google Scholar] [CrossRef]
  28. Wu, C.; Yang, H.; Zhang, S.; Han, P.; Sun, H.; Sheng, Z.; Yu, H.; Ma, X. The inhibition performance of anionic surfactant and zwitterionic surfactant toward the corrosion of carbon steel in NaCl solution. Int. J. Chem. Kinet. 2023, 55, 537. [Google Scholar] [CrossRef]
  29. Arkhipushkin, I.A.; Shikhaliev, K.S.; Potapov, A.Y.; Sapronova, L.V.; Kazansky, L.P. Inhibition of Brass (80/20) by 5-Mercaptopentyl-3-Amino-1,2,4-Triazole in Neutral Solutions. Metals 2017, 488, 3390. [Google Scholar] [CrossRef]
  30. Tkacz, J.; Slouková, K.; Minda, J.; Drábiková, J.; Fintová, S.; Doležal, P.; Wasserbauer, J. Influence of the Composition of the Hank’s Balanced Salt Solution on the Corrosion Behavior of AZ31 and AZ61 Magnesium Alloys. Metals 2017, 7, 465. [Google Scholar] [CrossRef]
Metals 14 01090 g001
Figure 1. (a) Polarization behaviors of Cu and Au and (b) ZRA test results of Cu coupled with Au in PCB etching solution.
Figure 1. (a) Polarization behaviors of Cu and Au and (b) ZRA test results of Cu coupled with Au in PCB etching solution.
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Figure 2. Surface images of (a) single Cu bare sample and (b) after etching of single Cu and (c) galvanic coupled Cu with Au in PCB etching solution.
Figure 2. Surface images of (a) single Cu bare sample and (b) after etching of single Cu and (c) galvanic coupled Cu with Au in PCB etching solution.
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Figure 3. AFM images of (a) single Cu bare sample and (b) after etching of single Cu and (c) galvanic coupled Cu with Au in PCB etching solution.
Figure 3. AFM images of (a) single Cu bare sample and (b) after etching of single Cu and (c) galvanic coupled Cu with Au in PCB etching solution.
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Figure 4. Effects of CTAB concentration on the galvanic corrosion rate of Cu coupled with Au at 25 °C in PCB etching solution.
Figure 4. Effects of CTAB concentration on the galvanic corrosion rate of Cu coupled with Au at 25 °C in PCB etching solution.
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Figure 5. Effects of betaine concentration on the galvanic corrosion rate of Cu coupled with Au at 25 °C in PCB etching solution.
Figure 5. Effects of betaine concentration on the galvanic corrosion rate of Cu coupled with Au at 25 °C in PCB etching solution.
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Figure 6. Polarization behaviors of (a) single Cu and (b) Au at 25 °C, depending on the presence or 0.9 mM CTAB in PCB etching solution.
Figure 6. Polarization behaviors of (a) single Cu and (b) Au at 25 °C, depending on the presence or 0.9 mM CTAB in PCB etching solution.
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Figure 7. Polarization behaviors of (a) single Cu and (b) Au at 25 °C, depending on the presence or 0.1 mM betaine in PCB etching solution.
Figure 7. Polarization behaviors of (a) single Cu and (b) Au at 25 °C, depending on the presence or 0.1 mM betaine in PCB etching solution.
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Table 1. Galvanic corrosion rate and inhibitor efficiency of Cu coupled with Au with the change in concentration of CTAB.
Table 1. Galvanic corrosion rate and inhibitor efficiency of Cu coupled with Au with the change in concentration of CTAB.
Concentration
of CTAB (mM)		icouple (Cu-Au)
(mA/cm2)		Inhibitor
Efficiency
No inhibitor3.26
0.6 0.45386.1%
0.9 0.25192.3%
1.20.47485.5%
Table 2. Galvanic corrosion rate and inhibitor efficiency of Cu coupled with Au with the change in concentration of betaine.
Table 2. Galvanic corrosion rate and inhibitor efficiency of Cu coupled with Au with the change in concentration of betaine.
Concentration
of Betaine (mM)		icouple (Cu-Au)
(mA/cm2)		Inhibitor
Efficiency
No inhibitor3.26
0.05 0.1495.7%
0.1 0.0399.1%
0.2 0.14695.5%
Table 3. Corrosion rate and corrosion potential of copper and gold with and without CTAB and betaine.
Table 3. Corrosion rate and corrosion potential of copper and gold with and without CTAB and betaine.
Cu Au
icorr (mA/cm2)Ecorr (mV)icorr (mA/cm2)Ecorr (mV)
Bare0.49−7.010.0991
CTAB0.028−840.386−172
Betaine0.0051−120.00742
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Shin, H.; Oh, S. Effects of CTAB (Cetyltrimethylammonium Bromide) and Betaine as Corrosion Inhibitors on the Galvanic Corrosion of Cu Coupled with Au on Print Circuit Board in Etching Solution. Metals 2024, 14, 1090. https://doi.org/10.3390/met14091090

AMA Style

Shin H, Oh S. Effects of CTAB (Cetyltrimethylammonium Bromide) and Betaine as Corrosion Inhibitors on the Galvanic Corrosion of Cu Coupled with Au on Print Circuit Board in Etching Solution. Metals. 2024; 14(9):1090. https://doi.org/10.3390/met14091090

Chicago/Turabian Style

Shin, HeeKwon, and SeKwon Oh. 2024. "Effects of CTAB (Cetyltrimethylammonium Bromide) and Betaine as Corrosion Inhibitors on the Galvanic Corrosion of Cu Coupled with Au on Print Circuit Board in Etching Solution" Metals 14, no. 9: 1090. https://doi.org/10.3390/met14091090

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