| 摘要 |
PURPOSE: To improve solderability of electronic components and a printed board, by recognizing metal oxide which loses solderability of electronic components, by using an electrochemical reducing method. CONSTITUTION: A through hole electrode 46 is positioned between O rings 26 and 36, and a circuit board 20 is fixed between franges 22 and 32. Inert gas is made to flow by opening a valve 45, and oxygen is eliminated from system. By closing the valve 45 and opening a valve 43, electrolyte 52 is sucked by vacuum into a chamber 42 containing the electrode 46 and a facing electrode 64, through a pipe 48. A system 62 supplies a current in a specific range to the electrodes 64, 46 and a through hole 66, through lines 63, 65 and the electrolyte 52, and induces electrochemical reduction to oxides on copper circuits on the electrode 46. The system 62 records the electrode potential between the electrode 46 and a reference electrode 60, as a time function, and reduces the potential to charge density. The indication of electrode potential/charge density show a series of inflection points or a height which indicate that specific oxide is being reduced, so that soldering characteristics of the circuit board can be known. |
