25 further the brush scrubbing apparatus preferably includes a current detector 51 which detects a driving current value of the brush spin motor 18 between the brush spin motor 18 and the second voltage supply circuit 31 the controller 53 controls responding to a signal from the current detector 51 the arm swing mechanism 15 the arm up and down mechanism 16 the first voltage supply circuit 6 and the second voltage supply circuit 31 a keyboard 55 is provided for inputting a data to the controller 53 in this apparatus the controller 53 is preferably a microprocessor which comprises cpu rom and ram for example fig2 is a flow chart showing an operation of a brush scrubbing apparatus according to a first preferred embodiment of a present invention as shown in fig2 the controller 53 inputs in advance a predetermined distance to thrust downward from a reference position that the brush contacts the semiconductor wafer and a cleaning time inputted by an operator via the keyboard see s 1 here the reference position is a position that the rotating brush 17 contacts to the semiconductor wafer 17 surface next the rotating turntable 1 horizontally retains the semiconductor wafer 2 thereon the semiconductor wafer 2 turns on a vertical axis at a predetermined rotation speed while supplying a deionized water to the semiconductor wafer 2 surface from the nozzle 3 the brush 17 moves above the semiconductor wafer 2 edge using the arm swing mechanism 15 at the.