PURPOSE: To prevent contaminants from being transferred without increasing the flow rate of a cleaning liquid by a method wherein a wafer carrier is provided with partition plates for partitioning the carrier into every one sheet of a wafer to house wafers between the partition plates.

CONSTITUTION: A wafer carrier 2 is provided with partition plates 3 for partitioning the carrier 2 into every one sheet of a wafer 1 to house wafers 1 between the partition plates 3 and a cleaning liquid is fed from the lower part of a cleaning tank 4 through a cleaning liquid feed pipe 6. The cleaning liquid passes between the wafers 1 from the side of the bottom of the carrier 2 to flow upward and overflows from the upper part of the tank 4. Thereby, contaminants separated from rears of the wafers in the cleaning liquid can be prevented from being readhered on the surfaces of the wafers without increasing the flow rate of the cleaning liquid.