Polishing apparatus

Abstract

A polishing apparatus 1 includes a control device 90 . The control device 90 performs: a cleaning process of causing a cleaning solution to flow in a flow channel 70 a and then causing a polishing solution to flow in the flow channel 70 a when the number of substrates Wf polished by a polishing machine 10 reaches a predetermined number; and a clogging detecting process of detecting whether clogging has occurred in the flow channel based on a pressure or a flow rate of the cleaning solution detected by sensors 60 and 61 when the cleaning solution flows in the flow channel.

1 . A polishing apparatus comprising:
 a polishing machine for polishing a substrate;   a flow channel for supplying a polishing solution or a cleaning solution to the polishing machine;   a switching device disposed in the flow channel and configured to switch between the polishing solution and the cleaning solution and to cause the solution to flow in the flow channel;   a sensor for detecting a pressure or a flow rate of the cleaning solution flowing in the flow channel; and   a control device,   wherein the control device performs:
 a cleaning process of controlling the switching device such that the cleaning solution flows in the flow channel and then controlling the switching device such that the polishing solution flows in the flow channel when the number of substrates polished by the polishing machine reaches a predetermined number; and 
 a clogging detecting process of detecting whether clogging has occurred in the flow channel based on the pressure or the flow rate of the cleaning solution detected by the sensor when the cleaning solution flows in the flow channel. 
   
     
     
         2 . The polishing apparatus according to  claim 1 , further comprising a flow rate adjusting device disposed at a position downstream from the switching device in the flow channel and configured to adjust a flow rate of the cleaning solution flowing in the flow channel to a predetermined range,
 wherein the sensor is a pressure sensor disposed at a position downstream from the flow rate adjusting device in the flow channel.   
     
     
         3 . The polishing apparatus according to  claim 2 , wherein the control device detects whether clogging has occurred in the flow channel based on a maximum value, an average value, or a minimum value of values of the pressure detected by the pressure sensor when the flow rate of the cleaning solution is in the predetermined range. 
     
     
         4 . The polishing apparatus according to  claim 2 , wherein the control device determines that clogging has occurred in the flow channel when the value of the pressure detected by the pressure sensor is equal to or greater than a preset first threshold value, and
 wherein the control device determines that a degree of clogging in the flow channel is low when the value of the pressure detected by the pressure sensor is equal to or greater than the first threshold value and is less than a second threshold value greater than the first threshold value and determines that a degree of clogging in the flow channel is high when the value of the pressure detected by the pressure sensor is equal to or greater than the second threshold value.   
     
     
         5 . The polishing apparatus according to  claim 1 , further comprising a notification device,
 wherein the control device causes the notification device to notify that clogging has occurred in the flow channel when detecting in the clogging detecting process that clogging has occurred in the flow channel.   
     
     
         6 . The polishing apparatus according to  claim 4 , wherein the control device prohibits the polishing machine from polishing a substrate when determining that a degree of clogging in the flow channel is high. 
     
     
         7 . The polishing apparatus according to  claim 1 , wherein the flow channel includes a single pipe, and
 wherein a downstream end of the flow channel is constituted by an end of the pipe.   
     
     
         8 . The polishing apparatus according to  claim 1 , wherein the flow channel includes a single pipe and a discharge nozzle connected to a downstream end of the pipe and including at least one discharge hole. 
     
     
         9 . The polishing apparatus according to  claim 1 , wherein the control device stores the number of substrates polished by the polishing machine whenever the polishing machine polishes the substrate, and
 wherein the control device resets the stored number of substrates to zero when the cleaning solution flows in the flow channel.