Study On Corrosion Inhibition Of Copper Layer Of Printed Circuit Board By Corrosion Inhibitor

Copper metal is widely used in the production of conductive patterns on printed circuit boards(Printed Circuit Board,PCB)because of its low resistivity,high reliability,and good ductility.In the PCB manufacturing process,the exposed copper surface and the chloride ion contact will cause corrosion of the copper surface,destroy signal integrity,cause rework and chargeback issues,and cause great economic losses to the enterprise.Therefore,proper anti-corrosion measures in the PCB manufacturing process are essential for obtaining good and qualified PCB products.Electrochemical studies have found that trimethylbenzothiazolium iodide MBI is an excellent cathode corrosion inhibitor.At the same time,the addition of MBI did not change the mechanism of copper corrosion at the cathode by H₂SO₄,but covered the reaction between copper and H₂SO₄.The active site is used to suppress copper corrosion.When the MBI concentration is 0.2m M,the corrosion current density drops to 0.84?Acm-2,the corrosion potential moves negatively to-117 m V/SCE,and the corrosion suppression efficiency reaches 94.80%.In the study of self-assembled membrane 6-(dibutylamino)-1,3,5-triazine-2,4-dithiol(TDD)-SAM,it was found that with the increase of self-assembly time and solution concentration,the current significantly increased.With the decline,TDD-SAM gradually suppressed the anodic dissolution of copper.Comparing the electrochemical impedance of TDD-modified copper and another triazine-based corrosion inhibitor TMTA-modified copper,it was found that TDD-SAM has better electrochemical performance.When the TDD concentration is 2 m M and the self-assembly time is 12 h,the The efficiency reached 97.91%respectively,and under the same circumstances,the corrosion inhibition efficiency of TMTA modified copper at 3.5%was only 90.55%,which indicates that the chain length can increase the corrosion inhibition performance of SAM,and macromolecule organic compounds are more easily adsorbed on the copper surface.Scanning electron microscopy and X-ray spectrometer scanning revealed that MBI has a very strong adsorption performance on the copper surface.Compared with the blank solution,copper has excellent corrosion resistance in a sulfuric acid solution containing a corrosion inhibitor.The scratches that are present after the grinding are clearly visible,which indicates that MBI blocks the attack of copper by oxygen and hydrogen ions by adsorbing on the copper surface.Fourier transform infrared spectroscopy and contact angle tests have shown that TDD can be adsorbed on the copper surface by self-assembly to form a dense organic protective hydrophobic film.Computer simulation results show that a large number of electron clouds are distributed around the N,S atoms and 6-membered heterocycles contained in the organic compounds MBI and TDD.The metallic copper hybrid orbits indicate that there are empty orbits that can accept lone pair electrons,which leads to MBI and TDD can be adsorbed on the copper surface in parallel,which better explains the mechanism of MBI and TDD adsorbed on the copper surface to inhibit its corrosion in corrosive media.