Plating apparatus

Abstract

Provided is a technique that allows ensuring an in-plane uniformity of film thickness of a substrate.A plating apparatus 1 includes auxiliary anodes 60a, 606, 60c, 60d. End portion proximal regions in an extending direction of the auxiliary anode are covered by resistive elements 65 having electrical conduction rates larger than zero, and the electrical conduction rates are lower than an electrical conduction rate of a plating solution. A region closer to a center than the end portion proximal regions of the auxiliary anode is not covered by the resistive element, and a surface of the region closer to the center than the end portion proximal regions of the auxiliary anode is exposed.

1 . A plating apparatus comprising:
 a plating tank configured to accumulate a plating solution and provided with an anode;   a substrate holder configured to hold a substrate as a cathode such that the substrate is opposed to the anode, the substrate being a polygonal substrate having a plurality of sides;   an intermediate mask arranged between the anode and the substrate inside the plating tank, the intermediate mask being provided with a hole that allows a current flowing between the anode and the substrate to pass therethrough; and   an auxiliary anode, wherein   the hole of the intermediate mask is a polygonal hole having a plurality of sides corresponding to the respective plurality of sides of the substrate,   the auxiliary anode is arranged between the substrate and the intermediate mask so as to correspond to at least one side of the hole of the intermediate mask, and the auxiliary anode extends in an extending direction of the side of the hole of the intermediate mask, and   end portion proximal regions of the auxiliary anode from both end portions in an extending direction of the auxiliary anode toward a center are covered by resistive elements having electrical conduction rates larger than zero, the electrical conduction rates are lower than an electrical conduction rate of the plating solution, a region closer to the center than the end portion proximal regions of the auxiliary anode is not covered by the resistive element, and a surface of the region closer to the center than the end portion proximal regions of the auxiliary anode is exposed.   
     
     
         2 . The plating apparatus according to  claim 1 , wherein
 the electrical conduction rates of the resistive elements decrease along from a central side toward end portion sides in the extending direction of the auxiliary anode covered by the resistive elements.   
     
     
         3 . The plating apparatus according to  claim 1 , wherein
 the resistive element has a plurality of holes, and   the electrical conduction rates of the resistive elements decrease along from the central side toward the end portion sides by a density of the holes of the resistive element decreasing along from the central side toward the end portion sides.   
     
     
         4 . The plating apparatus according to any one of  claim 1 , wherein
 lengths in the extending direction of the auxiliary anode of the end portion proximal regions of the auxiliary anode are a length of 10% or less of a total length of the auxiliary anode.   
     
     
         5 . The plating apparatus according to any one of  claim 1 , wherein
 the plating apparatus includes a housing portion configured to house the auxiliary anode inside the housing portion,   the housing portion is provided with an opening opened so as to face the substrate, and   the opening is closed by a membrane configured to allow metal ions included in the plating solution to pass through the membrane and inhibit oxygen generated from surfaces of the auxiliary anode from passing through the membrane.