PURPOSE: To uniformize the plating ion concn. on a sheet (semiconductor wafer, etc.) to be plated, to prevent the defective plating due to the deposition of bubbles and hydrogen bubbles, to secure contact of a cathode and to facilitate the attachment and detachment of the sheet to and from the plating device.

CONSTITUTION: A liq. storage chamber 9, a plating chamber 10 and a drain chamber 11 are successively provided, and an oblique upward current of a plating soln. 2 is formed in the plating chamber 10. An opening 12 is provided at the lower part of a partition plate 13, an anode plate 20 is fixed to the partition plate, and a seat plate 21 on which the back of a semiconductor wafer 1 is abutted is formed integrally with a weir 14. The lower end of a push plate 23 having a window 24 is fitted into a pit 25 provided at the bottom of the plating chamber 10, and the push plate is detained by a clamping means 26 at the upper part. A cathode needle 22 is elastically fixed to the inner periphery of the window 24, and then the semiconductor wafer 1 is pressed on the seat plate 21 when the cathode needle is mounted.