以無電鍍鎳銅磷合金方法改善PTFE表面銅箔耐蝕性能之研究

Study on the Improvement of the Corrosion Resistance of Copper Layer on PTFE by Electroless Deposition of Ni-Cu-P Alloy

為達聚四氟乙烯（PTFE）表面導電化，先以濕式化學法及錫鈀置換等敏化、活化步驟，再以無電鍍技術在其表面沈積銅金屬。PTFE具有良好的物性及電性，配合高導電度的銅層已被廣泛使用在高頻的應用上。但因銅層易被氧化產生腐蝕，故本研究嘗試導入鎳磷合金或鎳銅磷合金在PTFE表面以保護銅層，探討反應參數包括硫酸鎳及硫酸銅等反應物濃度對合金沈積速度的影響，並進行各項物性及功能量測，包括附著力及電性測試，利用EDX、SEM進行鍍層成份及表面型態分析，且藉由電化學方法量測鎳銅磷合金之極化曲線，以評估其耐蝕能力。實驗結果顯示，鎳銅磷合金的沈積速度會隨硫酸鎳濃度提高而增加，但硫酸銅濃度會抑制其反應速率。經由適當的操作條件，可在PTFE基材上得到鍍層結合力佳且具有良好耐蝕性之鎳銅磷合金鍍層。

For surface conduction on PTFE (polytetrafluoroethylene) substrate, the PTFE were sensitization through the activation of the palladium catalyst, followed by the electroless plating of copper. PTFE exhibits certain extraordinary characteristics including low dielectric constant, high thermal stability and good mechanical properties. As a result of high conductivity, the copper coated on PTFE is of great interest and value to printed circuit board (PCB), especially for high frequency applications. The combination of these properties makes the materials ideal for developing new printed wiring boards and integrated circuit packaging which require high frequency of working. One of the concerns in deposited copper is the corrosion resistance. In this investigation, Ni-Cu-P alloy is induced on copper layer to improve the corrosion resistance. The effect of the concentration of reactants in electroless plating baths on deposition rate and the content of deposited alloy has been studied. The adhesion and conductivity of deposits were measured. SEM micrographs showed the surface morphology of Ni-Cu-P alloy deposits and EDX determined the content ratio of the deposits. To find out the electrochemical behavior of the coatings, potentiodynamic polarization studies were carried out. The electrochemical parameters obtained from Tafel polarization curves and the corrosion current density values were clearly showed. The results showed that a good adhesion deposits of Ni-Cu-P was obtained and the corrosion resistance was improved.