Dynamic anode for semiconductor manufacturing

Abstract

An electrochemical deposition system includes a tank, a primary anode, and a secondary anode, all positioned within the tank. When a substrate is placed in the tank, the primary anode is situated at a distance from the substrate. The secondary anode is located closer to the substrate, positioned between the primary anode and the substrate. The secondary anode has one or more electrically active elements designed to affect the deposition process.

What is claimed is: 
     
         1 . An electrochemical deposition system comprising:
 a reactor wall at least partially defining a chamber configured to permit flow of electrolyte therethrough;   a primary anode;   a plating rotor configured to grip and suspend a substrate in the chamber, and provide a conductive path between the primary anode and the substrate such that when electrolyte fills the chamber, application of electrical potential to the primary anode and substrate results in the primary anode, substrate, and electrolyte forming an electrochemical cell, and the reactor wall and electrochemical cell forming a reactor; and   a secondary anode in the reactor between the primary anode and plating rotor and configured to alter a rate of plating angularly and radially along the substrate such that the rate in a vicinity of a perimeter of the substrate adjacent to the secondary anode changes as the substrate rotates within the reactor.   
     
     
         2 . The electrochemical deposition system of  claim 1 , wherein the secondary anode includes a single electrically active element. 
     
     
         3 . The electrochemical deposition system of  claim 1 , wherein the secondary anode includes a plurality of independently controllable electrically active elements. 
     
     
         4 . The electrochemical deposition system of  claim 1 , where the secondary anode is further configured to generate an electric field responsive to application of electrical potential to the secondary anode and substrate. 
     
     
         5 . The electrochemical deposition system of  claim 1 , wherein the primary anode and secondary anode are of a same material. 
     
     
         6 . The electrochemical deposition system of  claim 1 , wherein a material of the secondary anode and a plating material are same. 
     
     
         7 . The electrochemical deposition system of  claim 1  further comprising one or more controllers programmed to, during operation of the electrochemical cell, switch a polarity of the primary anode and substrate. 
     
     
         8 . The electrochemical deposition system of  claim 7 , wherein the one or more controllers are further programmed to match a polarity of the secondary anode to that of the primary anode or substrate. 
     
     
         9 . A method comprising:
 while applying an electrical potential to a primary anode and substrate of an electrochemical deposition system, activating selected electrically active elements of a secondary anode adjacent to the substrate, and located between the primary anode and substrate such that the selected electrically active elements generate electric fields that affect deposition on areas of the substrate in a vicinity of the selected electrically active elements.   
     
     
         10 . The method of  claim 9  further comprising varying a voltage applied to the selected electrically active elements. 
     
     
         11 . An electrochemical deposition system comprising:
 a tank;   primary and secondary anodes disposed within the tank such that the primary anode is spaced away from a substrate when the substrate is present in the tank, and the secondary anode is adjacent to the substrate and between the primary anode and substrate when the substrate is present in the tank, the secondary anode including a set of electrically active elements; and   a one or more controllers programmed to activate selected ones of the electrically active elements.   
     
     
         12 . The electrochemical deposition system of  claim 11 , wherein the set includes a single electrically active element. 
     
     
         13 . The electrochemical deposition system of  claim 11 , wherein the set includes a plurality of electrically active elements. 
     
     
         14 . The electrochemical deposition system of  claim 11 , wherein the primary and secondary anodes are of a same material. 
     
     
         15 . The electrochemical deposition system of  claim 11 , wherein a material of the secondary anode and a plating material are same.