Method and apparatus for cleaning substrate

Abstract

A substrate is cleaned by performing a scrubbing process on a surface to be cleaned of the rotating substrate with a roll-shaped cleaning member while holding an outer circumferential surface of the roll-shaped cleaning member in contact with the surface to be cleaned of the substrate across a predetermined contact width. During at least a part of the scrubbing process, the roll-shaped cleaning member is placed at an offset cleaning position where the central axis of the roll-shaped cleaning member is spaced from the central axis of the substrate by a distance which is 0.14 to 0.5 times the contact width. The surface to be cleaned of the substrate is scrubbed with more uniform cleaning intensity while taking into account the cleaning intensity at each position (area) along the radial direction of the surface to be cleaned of the substrate.

What is claimed is: 
     
         1 . A method of cleaning a substrate, comprising:
 performing a scrubbing process on a surface of a rotating substrate with a roll-shaped cleaning member by placing an outer circumferential surface of the roll-shaped cleaning member in contact with the surface of the substrate across a predetermined contact width which is a width in a direction perpendicular to a central axis of the roll-shaped cleaning member, the roll-shaped cleaning member being longer than a diameter of the substrate; and   during at least a part of the scrubbing process, placing the roll-shaped cleaning member at an offset cleaning position at which the central axis of the roll-shaped cleaning member is horizontally spaced from a central axis of the substrate in a direction perpendicular to the central axis of the roll-shaped cleaning member by a distance which is 0.14 to 0.5 times the predetermined contact width.   
     
     
         2 . The method according to  claim 1 , wherein the outer circumferential surface of the roll-shaped cleaning member has a plurality of nodules for contacting the surface of the substrate, the nodules being distributed so as to be progressively denser from a center toward outer ends of the roll-shaped cleaning member. 
     
     
         3 . A method of cleaning a substrate, comprising:
 performing a scrubbing process on a surface of a rotating substrate with a roll-shaped cleaning member by placing an outer circumferential surface of the roll-shaped cleaning member in contact with the surface of the substrate across a predetermined contact width which is a width in a direction perpendicular to a central axis of the roll-shaped cleaning member, the roll-shaped cleaning member being longer than a diameter of the substrate; and   during the scrubbing process, reciprocating the roll-shaped cleaning member that touches the surface of the substrate near a position where the central axis of the roll-shaped cleaning member and a central axis of the substrate cross each other, the roll-shaped cleaning member being reciprocated parallel to the surface of the substrate in directions perpendicular to the central axis of the roll-shaped cleaning member by a distance which is within 16 times the predetermined contact width.   
     
     
         4 . The method according to  claim 3 , wherein the roll-shaped cleaning member is controlled to move at a speed which is highest at the position where the central axis of the roll-shaped cleaning member and the central axis of the substrate cross each other. 
     
     
         5 . The method according to  claim 3 , wherein the roll-shaped cleaning member is controlled to move at a speed which is inversely proportional to the distance by which the roll-shaped cleaning member is spaced from the position where the central axis of the roll-shaped cleaning member and the central axis of the substrate cross each other, and which has a maximum moving speed and a minimum moving speed at a ratio ranging from 3 to 11. 
     
     
         6 . The method according to  claim 3 , wherein the outer circumferential surface of the roll-shaped cleaning member has a plurality of nodules for contacting the surface of the substrate, the nodules being distributed so as to be progressively denser from a center toward outer ends of the roll-shaped cleaning member. 
     
     
         7 . A method of cleaning a substrate, comprising:
 performing a scrubbing process on a surface of a rotating substrate with a roll-shaped cleaning member by placing an outer circumferential surface of the roll-shaped cleaning member in contact with the surface of the substrate across a predetermined contact width which is a width in a direction perpendicular to a central axis of the roll-shaped cleaning member, the roll-shaped cleaning member being longer than a diameter of the substrate; and   during the scrubbing process, causing the roll-shaped cleaning member to stay at cleaning positions for respective predetermined times, the cleaning positions being spaced from each other in a direction perpendicular to the central axis of the roll-shaped cleaning member,   wherein at least one of the cleaning positions comprises an offset cleaning position at which the central axis of the roll-shaped cleaning member is spaced from a central axis of the substrate.   
     
     
         8 . The method according to  claim 7 , wherein the cleaning positions include a plurality of offset cleaning positions, and the time during which the roll-shaped cleaning member stays in each of the plurality of offset cleaning positions is proportional to a distance between each of the plurality of offset cleaning positions and the central axis of the substrate. 
     
     
         9 . The method according to  claim 7 , wherein the outer circumferential surface of the roll-shaped cleaning member has a plurality of nodules for contacting the surface of the substrate, the nodules being distributed so as to be progressively denser from a center toward outer ends of the roll-shaped cleaning member.