Gas dissolved water producing apparatus and method thereof and ultrasonic cleaning equipment and method thereof

Abstract

A gas dissolved water producing apparatus includes a gas dissolving section, a gas channel for guiding a gas into the dissolving section, a first water channel for guiding water into the dissolving section, a gas dissolved water discharge channel, and a second water channel for guiding the water without passing through the dissolving section. The second water channel joins the gas dissolved water discharge channel to control the solution gas dissolved in the gas dissolved water can be controlled to a prescribed level of concentration.

1 - 13 . (canceled)  
     
     
         14 . A polishing apparatus comprising: 
 a rotatable chuck including chuck pawls to be clamped to a periphery of a semiconductor wafer so as to hold the semiconductor wafer;    a cleaning liquid ejecting nozzle for ejecting a cleaning liquid against a surface of the semiconductor wafer held by said rotatable chuck while said rotatable chuck rotates; and    an ultrasonic cleaning device for cleaning the semiconductor wafer using gas-dissolved water having a solution gas concentration no greater than a saturated solution gas concentration.    
     
     
         15 . The polishing apparatus of  claim 14 , wherein said ultrasonic cleaning device includes a gas-dissolved water producing apparatus including: 
 a dissolving section for dissolving a solution gas into water to form gas-dissolved water;    a solution gas supply channel for guiding the solution gas into said dissolving section;    a water supply channel for guiding the water, said water supply channel including: 
 a first supply channel for guiding the water into said dissolving section; and  
 a second supply channel for guiding the water around said dissolving section so that the water does not pass through said dissolving section, said second supply channel being branched off from said first supply channel so as to form a bypass around said dissolving section;  
   a gas-dissolved water discharge channel for guiding the gas-dissolved water from said dissolving section, said second supply channel communicating with said gas-dissolved waterdischarge channel so that the water bypassed around said dissolving section flows into the gas-dissolved water to thereby dilute the gas-dissolved water;    a flow rate regulator arranged in said gas-dissolved water discharge channel downstream of said dissolving section, for regulating a flow of the water guided through said water supply channel; and    a dissolved solution gas concentration meter for measuring the solution gas concentration of the gas-dissolved water in said gas-dissolved water discharge channel.    
     
     
         16 - 18 . (canceled)  
     
     
         19 . A polishing method comprising: 
 polishing a semiconductor wafer;    after said polishing, securely clamping a periphery of the semiconductor wafer using chuck pawls of a rotatable chuck so that the semiconductor wafer is held by the rotatable chuck with a surface to be cleaned facing upwards;    rotating the rotatable chuck;    ejecting cleaning liquid from a cleaning liquid ejecting nozzle against the surface of the semiconductor wafer facing upwards so as to wash off debris from the surface of the semiconductor wafer; and    cleaning the semiconductor wafer with an ultrasonic cleaning device using gas-dissolved water having a solution gas concentration no greater than a saturated solution gas concentration.    
     
     
         20 . The polishing method of  claim 19 , wherein said cleaning of the semiconductor wafer with an ultrasonic cleaning device using gas-dissolved water comprises producing gas-dissolved water using a gas-dissolved water producing apparatus, including: 
 a dissolving section for dissolving a solution gas into water to form gas-dissolved water;    a solution gas supply channel for guiding the solution gas into said dissolving section; a water supply channel for guiding the water, said water supply channel including: 
 a first supply channel for guiding the water into said dissolving section; and  
 a second supply channel for guiding the water around said dissolving section so that the water does not pass through said dissolving section;  
   a gas-dissolved water discharge channel for guiding the gas-dissolved water from said dissolving section, said second supply channel communicating with said gas-dissolved water discharge channel so that the water that does not pass through said dissolving section flows into the gas-dissolved water to thereby dilute the gas-dissolved water;    a flow rate regulator arranged in said water supply channel, for regulating a flow of the water guided through said water supply channel;    a dissolved solution gas concentration meter for measuring a solution gas concentration of the gas-dissolved water in said gas-dissolved water discharge channel; and    a controller for controlling said flow rate regulator based on the solution gas concentration measured by said dissolved solution gas concentration meter.    
     
     
         21 - 25 . (canceled)