Method of filling a deep etch feature

Abstract

A method for anisotropically plasma etching a semiconductor wafer is disclosed. The method comprises supporting a wafer in an environment operative to form a plasma, such as a plasma reactor, and providing an etching mixture to the environment. The etching mixture comprises at least one etch component, at least one passivation component, and at least one passivation material removal component.

1 . A method of filling a deep etch feature in a wafer with a metal comprising performing metal vapor deposition of a seed layer of the metal on a bottom wall of the deep etch feature. 
     
     
         2 . The method of  claim 1 , wherein the metal vapor deposition of a seed layer comprises:
 placing the wafer in a copper hexafluroacetylacetonate (CuHFAC) oven at 150° C.; and   bubbling helium through a CuHFAC Tri-methylvinylsilyl (CuHFAC-TMVS) precursor held at 40° C. to carry a copper precursor into a process chamber of the CuHFAC oven to expose the wafer to the copper precursor.   
     
     
         3 . The method of  claim 1 , wherein the seed layer is deposited on a metallic bottom wall of the deep etch feature. 
     
     
         4 . The method of  claim 1 , wherein the metal vapor is a copper vapor. 
     
     
         5 . The method of  claim 4 , wherein the copper vapor is formed using a copper HFAC process. 
     
     
         6 . The method of  claim 1 , wherein the metal comprises aluminum or copper. 
     
     
         7 . The method of  claim 1 , wherein the deep etch feature comprises a via hole. 
     
     
         8 . The method of  claim 1 , further comprising filling the deep etch feature with a first metal. 
     
     
         9 . The method of  claim 8 , wherein the first metal comprises copper. 
     
     
         10 . The method of  claim 8 , further comprising placing the wafer in an electroless bath in order to fill the deep etch feature. 
     
     
         11 . The method of  claim 10 , wherein the electroless bath comprises an electroless copper plating bath with copper electroless plating solution. 
     
     
         12 . The method of  claim 8 , further comprising filling an unfilled portion of the deep etch feature with a second metal disposed on the first metal. 
     
     
         13 . The method of  claim 12 , wherein the second metal comprises gold. 
     
     
         14 . A method for filling a deep etch feature in a wafer with a metal comprising depositing metal vapor on a bottom wall of the deep etch feature to form a seed layer of metal thereon. 
     
     
         15 . The method of  claim 14 , wherein depositing metal vapor comprises:
 placing the wafer in a copper hexafluroacetylacetonate (CuHFAC) oven at 150° C.; and   bubbling helium through a CuHFAC tri-methylvinylsilyl (CuHFAC-TMVS) precursor held at 40° C. to carry a copper precursor into a process chamber of the oven to expose the wafer to the copper precursor.   
     
     
         16 . The method of  claim 14 , further comprising filling the deep etch feature with a first metal. 
     
     
         17 . The method of  claim 16 , wherein filling the deep etch feature comprises electroless plating. 
     
     
         18 . The method of  claim 17 , wherein the electroless plating comprises placing the wafer in an electroless bath which comprises an electroless copper plating bath of copper electroless plating solution. 
     
     
         19 . A wafer formed by the method of  claim 1 . 
     
     
         20 . A wafer formed by the method of  claim 14 .