| 摘要 |
PURPOSE:To remove selectively copper oxide film in a short time without causing etching on the surface of Cu plate, by dipping the Cu plate in an aqueous soln. of H3PO2 of specific concn., and by applying supersonic vibration to the soln. CONSTITUTION:Cu plate is dipped in an aqueous H3PO2 soln. 1-5% by volume in concn. at a temp. from ordinary temp. to about 40 deg.C. Then supersonic wave oscillation not lower than 10kHz, ordinarily about 30kHz, is applied to the soln. Hereby, only copper oxide film (CuO, Cu2O) is removed in a short time, and no troubles such as corrosion of the Cu plate due to remaining soln. are caused. |
