Apparatus and method for electrochemical processing of thin films on resistive substrates

Abstract

An electrochemical process comprising: providing a 125 mm or larger semiconductor wafer in electrical contact with a conducting surface, wherein at least a portion of the semiconductor wafer is in contact with an electrolytic solution, said semiconductor wafer functioning as a first electrode; providing a second electrode in the electrolytic solution, the first and second electrode connected to opposite ends of an electric power source; and irradiating a surface of the semiconductor wafer with a light source as an electric current is applied across the first and the second electrodes. The invention is also directed to an apparatus including a light source and electrochemical components to conduct the electrochemical process.

1 . An anodic electrochemical process of a 125 mm or larger, n-type semiconductor wafer with a metal layer, the process comprising:
 positioning the 125 mm or larger, n-type semiconductor wafer in an electrolytic solution;   positioning a counter electrode in the electrolytic solution;   illuminating a front side or the back side of the n-type semiconductor wafer with a light source; and   applying an electric current to the semiconductor wafer and to the counter electrode.   
     
     
         2 . The process of  claim 1  wherein the anodic electrochemical process is an electroetching process of the metal layer or an anodization process of the metal layer disposed on the semiconductor wafer. 
     
     
         3 . The process of  claim 1  wherein the electrochemical process is an electroetch or anodizing process, and the semiconductor wafer comprises one or more metals selected from Al, Ti, Zr, Nb, Hf, Ta, W, Mo and Cd, or the semiconductor wafer is a semiconductor wafer comprising Si, Ge, In, Ga, Sb, P and any combination thereof. 
     
     
         4 . The process of  claim 3  wherein the electric current is applied as a constant current, constant potential, a pulse current or a pulse potential. 
     
     
         5 . An apparatus comprising:
 a tank for holding an electrolytic solution;   a conducting surface in contact with a surface of a semiconductor wafer, said conducting surface in electrical contact with an electric power source;   a light source facing an opposite surface of the semiconductor wafer; and   an electrode in electrical contact with the electric power source, wherein the electrode is positioned in the tank so that the electrode can come in contact with the electrolytic solution.