Plating apparatus

Abstract

An objective of the present invention is to provide a plating apparatus capable of improving uniformity of a plating film formed on a substrate. The plating apparatus includes a first potential sensor disposed at a first position in a region between a substrate held by a substrate holder and an anode, a second potential sensor disposed at a second position outside the region between the substrate held by the substrate holder and the anode, and a third potential sensor disposed at a third position different from the second position and outside the region between the substrate held by the substrate holder and the anode. The plating apparatus measures a first potential difference that is a potential difference between the first position and the second position, and a second potential difference that is a potential difference between the second position and the third position and measures a film thickness of the plating film based on a difference between the first potential difference and the second potential difference.

What is claimed is: 
     
         1 . A plating apparatus comprising:
 a plating tank,   a substrate holder that holds a substrate,   an anode disposed, in the plating tank, facing the substrate held by the substrate holder, and   a film thickness measuring module including a sensor that detects a parameter related to a plating film formed on a surface to be plated of the substrate, the film thickness measuring module measuring a film thickness of the plating film based on a detection value of the sensor during a plating treatment, wherein the sensor comprises:
 a first potential sensor disposed at a first position in a region between the substrate held by the substrate holder and the anode, 
 a second potential sensor disposed at a second position outside the region between the substrate held by the substrate holder and the anode, and 
 a third potential sensor disposed at a third position different from the second position and outside the region between the substrate held by the substrate holder and the anode, and 
   the film thickness measuring module measures a first potential difference that is a potential difference between the first position and the second position, and a second potential difference that is a potential difference between the second position and the third position and measures the film thickness of the plating film based on a difference between the first potential difference and the second potential difference.   
     
     
         2 . The plating apparatus according to  claim 1 , wherein the film thickness measuring module is configured to estimate a distribution of a plating current in the substrate during the plating treatment based on the difference between the first potential difference and the second potential difference. 
     
     
         3 . The plating apparatus according to  claim 2 , wherein the film thickness measuring module is configured to estimate a film thickness distribution of the plating film in the substrate based on the estimated distribution of the plating current in the substrate. 
     
     
         4 . The plating apparatus according to  claim 1 , further comprising:
 a resistor disposed between the anode and the substrate, wherein the first potential sensor is disposed between the resistor and the substrate held by the substrate holder.   
     
     
         5 . The plating apparatus according to  claim 1 , further comprising:
 a plating condition adjustment module that adjusts plating conditions based on the film thickness of the plating film that is measured by the film thickness measuring module during the plating treatment.   
     
     
         6 . The plating apparatus according to  claim 5 , further comprising:
 a shielding body that is movable to a shielding position interposed between the surface to be plated of the substrate and the anode, and a retreated position retreated from between the surface to be plated of the substrate and the anode, wherein the plating condition adjustment module adjusts a position of the shielding body as the adjustment of the plating conditions.   
     
     
         7 . The plating apparatus according to  claim 5 , comprising:
 a resistor disposed between the anode and the substrate, and   a drive mechanism to change a distance between the substrate and the resistor, wherein the plating condition adjustment module changes the distance between the substrate and the resistor as the adjustment of the plating conditions.   
     
     
         8 . The plating apparatus according to  claim 5 , further comprising:
 an anode mask disposed above the anode, the anode mask having an opening dimension that is changeable, wherein the plating condition adjustment module changes the opening dimension of the anode mask as the adjustment of the plating conditions.   
     
     
         9 . The plating apparatus according to  claim 1 , further comprising:
 a rotation mechanism that rotates the substrate holder, wherein the film thickness measuring module is configured to measure the film thickness of the plating film, with the rotation of the substrate by the rotation mechanism.   
     
     
         10 . The plating apparatus according to  claim 1 , wherein a plurality of first potential sensors are provided from an outer circumference to an inner circumference of the substrate. 
     
     
         11 . The plating apparatus according to  claim 1 , wherein a plurality of first potential sensors are provided along an outer edge of the substrate. 
     
     
         12 . The plating apparatus according to  claim 1 , wherein the film thickness measuring module is configured to move the first potential sensor along a plate surface of the substrate during the plating treatment. 
     
     
         13 . The plating apparatus according to  claim 1 , wherein the substrate holder is configured to hold the substrate with the surface to be plated being oriented downward in the plating tank. 
     
     
         14 . The plating apparatus according to  claim 1 , wherein the substrate holder is configured to hold the substrate with the surface to be plated being oriented to a side in the plating tank.