Apparatus and method for cleaning semiconductor wafers
First Claim
1. A method for the cleaning treatment of a semiconductor wafer in an apparatus comprising:
- (a) a rectangular or square vessel to contain an aqueous medium for cleaning of a semiconductor wafer by holding the semiconductor wafer as a workpiece in a substantially vertical disposition in the center part thereof, said vessel being partitioned in a lengthwise direction into an anode compartment at the center and a pair of cathode compartments on both sides of the anode compartment;
(b) a pair of partitions each partitioning the anode compartment and one of the cathode compartments, each partition being formed of a pair of hydrogen-ion exchange membranes, one, facing the anode compartment and, the other, facing the cathode compartment, to form a flow passage therebetween;
(c) a pair of anode plates each bonded to one of the ion exchange membranes on the surface facing the anode compartment; and
(d) a pair of cathode plates each bonded to one of the ion exchange membranes on the surface facing the cathode compartment at such a position approximately to oppose to the anode plate, which comprises the steps of;
(A) holding a semiconductor wafer in the anode compartment in a substantially vertical disposition;
(B) introducing pure water continuously into each of the anode compartment, cathode compartments and flow passages at the bottom thereof;
(C) discharging the pure water continuously from each of the cathode compartment, anode compartments and flow passages at the top thereof; and
(D) applying a direct-current voltage between the anode plate and the cathode plate.
1 Assignment
0 Petitions
Accused Products
Abstract
An improvement is proposed in the cleaning treatment of semiconductor silicon wafers in which the conventional step of cleaning with an aqueous solution of an acid is replaced with a cleaning treatment with a temporarily acidic pure water which is produced electrolytically by the application of a DC voltage between an anode and a cathode bonded to the surfaces of a hydrogen-ion exchange membrane so that the acidic cleaning treatment can be performed under mild conditions so as to eliminate the troubles unavoidable in the conventional process. The apparatus used therefor comprises a rectangular vessel partitioned into a central anode compartment, in which the wafers are held in a vertical disposition within an upflow of pure water, and a pair of cathode compartments on both sides of the anode compartment by partitioning with a pair of hydrogen-ion exchange membranes, on both sides of which an anode plate and a cathode plate are bonded.
80 Citations
14 Claims
-
1. A method for the cleaning treatment of a semiconductor wafer in an apparatus comprising:
-
(a) a rectangular or square vessel to contain an aqueous medium for cleaning of a semiconductor wafer by holding the semiconductor wafer as a workpiece in a substantially vertical disposition in the center part thereof, said vessel being partitioned in a lengthwise direction into an anode compartment at the center and a pair of cathode compartments on both sides of the anode compartment; (b) a pair of partitions each partitioning the anode compartment and one of the cathode compartments, each partition being formed of a pair of hydrogen-ion exchange membranes, one, facing the anode compartment and, the other, facing the cathode compartment, to form a flow passage therebetween; (c) a pair of anode plates each bonded to one of the ion exchange membranes on the surface facing the anode compartment; and (d) a pair of cathode plates each bonded to one of the ion exchange membranes on the surface facing the cathode compartment at such a position approximately to oppose to the anode plate, which comprises the steps of; (A) holding a semiconductor wafer in the anode compartment in a substantially vertical disposition; (B) introducing pure water continuously into each of the anode compartment, cathode compartments and flow passages at the bottom thereof; (C) discharging the pure water continuously from each of the cathode compartment, anode compartments and flow passages at the top thereof; and (D) applying a direct-current voltage between the anode plate and the cathode plate. - View Dependent Claims (2, 3)
-
-
4. A method for the cleaning treatment of a semiconductor wafer in an apparatus comprising:
-
(a) a rectangular or square vessel to contain an aqueous medium for cleaning of a semiconductor wafer by holding the semiconductor wafer as a workpiece in a substantially vertical disposition in a center part thereof, said vessel being partitioned in the lengthwise direction into an anode compartment at the center and a pair of cathode compartments on both sides of the anode compartment; (b) a pair of hydrogen-ion exchange membranes each partitioning the anode compartment and one of the cathode compartments; (c) a pair of anode plates each bonded to one of the ion exchange membranes on the surface facing the anode compartment; and (d) a pair of cathode plates each bonded to one of the ion exchange membranes on the surface facing the cathode compartment at such a position approximately to oppose to the anode plate, which comprises the steps of; (A) holding a semiconductor wafer in the anode compartment in a substantially vertical disposition; (B) introducing pure water continuously into each of the anode compartment and cathode compartments at the bottom thereof; (C) discharging the pure water continuously from each of the anode compartment and cathode compartments at the top thereof; and (D) applying a direct-current voltage between the anode plate and the cathode plate. - View Dependent Claims (5, 6)
-
-
7. A method for the cleaning treatment of a semiconductor wafer in an apparatus comprising:
-
(a) a rectangular or square vessel to contain an aqueous medium for cleaning of a semiconductor wafer by holding the semiconductor wafer as a workpiece in a substantially vertical disposition in a center part thereof, said vessel being partitioned in the lengthwise direction into a center compartment at the center and a pair of side compartments on both sides of the center compartment; (b) a pair of partitions each made of a hydrogen-ion exchange membrane partitioning the center compartment and one of the side compartments; (c) a first pair of electrode plates each bonded to one of the partitions on the surface facing the center compartment; and (d) a second pair of electrode plates each bonded to one of the partitions on the surface facing the side compartment at such a position approximately to oppose to the electrode plate of the first pair, which comprises the steps of; (A) holding a semiconductor wafer in the center compartment in a substantially vertical disposition; (B) introducing pure water continuously into each of the center compartment and side compartments at the bottom thereof; (C) discharging the pure water continuously from each of the center compartment and side compartments at the top thereof; and (D) applying a direct-current voltage between the electrode plates of the first pair and the second pair, the electrode plates of the first and the second pairs being the anode and cathode, respectively. - View Dependent Claims (8, 9, 10, 11, 12)
-
-
13. A method for the cleaning treatment of a semiconductor wafer in an apparatus comprising:
-
(a) a rectangular or square vessel to contain an aqueous medium for cleaning of a semiconductor wafer by holding the semiconductor wafer as a workpiece in a substantially vertical disposition in a center part thereof, said vessel being partitioned in the lengthwise direction into an anode compartment at the center and a pair of cathode compartments on both sides of the anode compartment; (b) a pair of hydrogen-ion exchange membranes each partitioning the anode compartment and one of the cathode compartments; (c) a pair of anode plates each bonded to one of the ion exchange membranes on the surface facing the anode compartment; (d) a pair of cathode plates each bonded to one of the ion exchange membranes on the surface facing the cathode compartment at such a position approximately to oppose to the anode plate; and (e) a pair of hydrogen ion-permeable membrane each forming a sub-compartment between the anode compartment and one of the anode plates, which comprises the steps of; (A) holding a semiconductor wafer in the anode compartment in a substantially vertical disposition; (B) introducing pure water continuously into each of the anode compartment and cathode compartments at the bottom thereof; (C) discharging the pure water continuously from each of the anode compartment and cathode compartments at the top thereof; (D) introducing an aqueous solution of an electrolyte continuously into each of the sub-compartments at the bottom thereof; (E) discharging the aqueous solution of an electrolyte continuously from the sub-compartment at the top thereof; and (F) applying a direct-current voltage between the anode plate and the cathode plate. - View Dependent Claims (14)
-
Specification