Edge zone coating removal with warpage compensation

Abstract

An apparatus to remove at least a portion of a coating from a coated surface of a substrate may include a nozzle assembly and one or more nozzle-heads. Each nozzle-head may include at least one nozzle tip and a cavity configured to receive a portion of the coated surface of the substrate. The nozzle tip may be configured to direct an angled stream of an etchant on the substrate as the nozzle assembly moves along the length of the substrate. One or more sensors may measure a warpage of the substrate along the length of the substrate, and a controller may move the nozzle-head orthogonal to the direction of nozzle-head movement based on the measured warpage.

What is claimed is: 
     
         1 . An apparatus to remove at least a portion of a coating from a coated surface of a substrate, comprising:
 a nozzle assembly configured to travel in a first direction along a length of the substrate, the nozzle assembly including one or more nozzle-heads, wherein each nozzle-head of the one or more nozzle-heads includes,
 a body having a cavity, the cavity being configured to receive at least a portion of the coated surface of the substrate therein; and 
 at least one nozzle tip supported on the body and inclined at an obtuse angle with respect to the coated surface of the substrate received in the cavity, wherein the at least one nozzle tip is configured to direct an angled stream of an etchant to impinge on the coated surface of the substrate received in the cavity as the nozzle assembly travels in the first direction along the length of the substrate; 
   one or more sensors configured to measure a warpage of the substrate along at least a portion of the length of the substrate; and   a controller configured to move at least one nozzle-head of the one or more nozzle-heads in a second direction orthogonal to the first direction based on the measured warpage as the nozzle assembly travels in the first direction with the angled stream of the etchant impinging on the coated surface of the substrate received in the cavity.   
     
     
         2 . The apparatus of  claim 1 , wherein the at least one nozzle tip is inclined at an angle between 40-50 degrees with respect to the coated surface of the substrate. 
     
     
         3 . The apparatus of  claim 1 , wherein the one or more sensors are configured to measure the warpage of the substrate as the nozzle assembly travels in the first direction with the angled stream of the etchant impinging on the coated surface of the substrate. 
     
     
         4 . The apparatus of  claim 1 , wherein the controller is configured to continuously move the at least one nozzle-head in the second direction as the nozzle assembly travels in the first direction. 
     
     
         5 . The apparatus of  claim 1 , wherein the one or more sensors include a pair of sensors positioned on opposite sides of the substrate, wherein the pair of sensors are collectively configured to measure a variation in thickness of the substrate along at least the portion of the length of the substrate. 
     
     
         6 . The apparatus of  claim 5 , wherein the controller is further configured to move the at least one nozzle-head in a third direction orthogonal to the first direction and the second direction based on the measured variation in thickness of the substrate as the nozzle assembly travels in the first direction with the angled stream of the etchant impinging on the coated surface of the substrate. 
     
     
         7 . The apparatus of  claim 1 , wherein the at least one nozzle tip includes a pair of nozzle tips configured to direct angled streams of the etchant to impinge on opposite sides of the substrate received in the cavity. 
     
     
         8 . The apparatus of  claim 1 , wherein the one or more sensors are positioned ahead of the nozzle assembly in the first direction. 
     
     
         9 . The apparatus of  claim 1 , wherein the one or more sensors extend from the nozzle assembly in a third direction orthogonal to the first direction and the second direction. 
     
     
         10 . The apparatus of  claim 1 , wherein the nozzle assembly further includes an annular duct defined around the at least one nozzle tip, wherein the annular duct is configured to discharge a pressurized gas to form a gas shroud around the angled stream of the etchant impinging on the coated surface. 
     
     
         11 . The apparatus of  claim 1 , wherein the nozzle assembly further includes a suction cup coupled to a vacuum pump, wherein the suction cup is positioned within the cavity and configured to extract the etchant impinging on the coated surface from the nozzle assembly. 
     
     
         12 . The apparatus of  claim 1 , wherein the one or more nozzle-heads of the nozzle assembly includes multiple nozzle-heads stacked in the first direction. 
     
     
         13 . The apparatus of  claim 12 , wherein the controller is configured to move at least one nozzle-head of the multiple nozzle-heads in the second direction independent of another nozzle-head of the multiple nozzle-heads. 
     
     
         14 . A method of etching a coating from an edge of a coated surface of a substrate, comprising:
 measuring warpage of the substrate along a length of the substrate;   positioning the edge of the coated surface of the substrate in a cavity of a nozzle assembly, wherein the nozzle assembly includes one or more nozzle-heads with each nozzle head of the one or more nozzle-heads including at least one nozzle tip inclined at an obtuse angle with respect to the coated surface positioned in the cavity;   moving the nozzle assembly in a first direction along the length of the substrate with the at least one nozzle tip directing an angled stream of an etchant to impinge on the coated surface positioned in the cavity to etch the coating on the coated surface along the length of the substrate; and   moving at least one nozzle-head of the one or more nozzle-heads in a second direction orthogonal to the first direction based on the measured warpage while etching the coating along the length of the substrate.   
     
     
         15 . The method of  claim 14 , wherein measuring the warpage occurs while the at least one nozzle tip is discharging etchant to etch the coating. 
     
     
         16 . The method of  claim 14 , further including moving the nozzle assembly in the first direction along the length of the substrate to measure the warpage of the substrate while the at least one nozzle tip is not discharging etchant. 
     
     
         17 . The method of  claim 14 , wherein measuring the warpage of the substrate along the length of the substrate includes measuring a variation in thickness of the substrate along the length of the substrate, and the method further includes moving the at least one nozzle-head in a third direction orthogonal to the first direction and the second direction based on the measured variation in thickness of the substrate while etching the coating along the length of the substrate. 
     
     
         18 . The method of  claim 14 , wherein moving the at least one nozzle-head in the second direction includes continuously moving the at least one nozzle-head in the second direction while etching the coating along the length of the substrate. 
     
     
         19 . The method of  claim 14 , wherein the one or more nozzle-heads of the nozzle assembly includes multiple nozzle-heads stacked in the first direction, and wherein moving the at least one nozzle-head in the second direction includes moving a first nozzle-head of the multiple nozzle-heads in the second direction independent of a second nozzle-head of the multiple nozzle-heads. 
     
     
         20 . The method of  claim 14 , wherein the at least one nozzle tip includes a pair of nozzle tips positioned on opposite sides of the substrate positioned in the cavity, and wherein moving the nozzle assembly in the first direction includes the pair of nozzle tips simultaneously directing angled streams of the etchant to impinge on opposite surfaces of substrate positioned in the cavity.