Deposition of pure metals in 3d structures

Abstract

A system and method generate atomic hydrogen (H) for deposition of a pure metal in a three-dimensional (3D) structure. The method includes forming a monolayer of a compound that includes the pure metal. The method also includes depositing the monolayer on the 3D structure and immersing the 3D structure with the monolayer in an electrochemical cell chamber including an electrolyte. Applying a negative bias voltage to the 3D structure with the monolayer and a positive bias voltage to a counter electrode generates atomic hydrogen from the electrolyte and deposits the pure metal from the monolayer in the 3D structure.

What is claimed is: 
     
         1 . A method of generating atomic hydrogen (H) for deposition of a pure metal in a three-dimensional (3D) structure, the method comprising:
 forming a monolayer of a compound that includes the pure metal;   depositing the monolayer on the 3D structure;   immersing the 3D structure with the monolayer in an electrochemical cell chamber including an electrolyte; and   applying a negative bias voltage to the 3D structure with the monolayer and a positive bias voltage to a counter electrode to generate atomic hydrogen from the electrolyte and deposit the pure metal from the monolayer in the 3D structure.   
     
     
         2 . The method according to  claim 1 , wherein the forming the monolayer is performed in a soak chamber of an electrochemical cell. 
     
     
         3 . The method according to  claim 2 , wherein the forming the monolayer includes forming the monolayer of TiCl 4  by introducing TiCl 4  vapor with N 2  or Ar carrier gas into the soak chamber. 
     
     
         4 . The method according to  claim 2 , further comprising transferring the 3D structure to the electrochemical cell to perform the depositing the monolayer on the 3D structure. 
     
     
         5 . The method according to  claim 1 , wherein the immersing the 3D structure includes immersing the 3D structure in the electrolyte comprising H 2 O and HCl. 
     
     
         6 . The method according to  claim 5 , wherein the applying the negative bias voltage to the 3D structure causes H 30  to move toward the 3D structure to form atomic H for the deposition of the pure metal from the monolayer. 
     
     
         7 . The method according to  claim 1 , wherein the 3D structure is a silicon wafer. 
     
     
         8 . A system to deposit a pure metal in a three-dimensional (3D) structure, the apparatus comprising:
 an electrochemical cell comprising a soak chamber in which a monolayer of a compound including the pure metal is deposited on the 3D structure, and an electrolysis chamber in which atomic hydrogen (H) is generated at the 3D structure to facilitate deposition of the pure metal from the monolayer in the 3D structure.   
     
     
         9 . The system according to  claim 8 , further comprising inlets in the soak chamber configured to take in TiCl 4  vapor with N 2  or Ar carrier gas to form the monolayer of TiCl 4 . 
     
     
         10 . The system according to  claim 8 , further comprising a buffer zone between the soak chamber and the electrolysis chamber. 
     
     
         11 . The system according to  claim 10 , further comprising a robotic mechanism to transfer the 3D structure into the buffer zone of the electrochemical cell without introducing an air break. 
     
     
         12 . The system according to  claim 11 , further comprising surface pumps coupled to each of the soak chamber, the buffer zone, and the electrolysis chamber. 
     
     
         13 . The system according to  claim 12 , further comprising a controller configured to control at least one of the robotic mechanism or the surface pumps. 
     
     
         14 . The system according to  claim 8 , wherein the electrolysis chamber comprises an electrolyte including H 2 O and HCl. 
     
     
         15 . The system according to  claim 8 , further comprising a voltage supply, wherein a negative bias voltage generated from the voltage supply is applied to the 3D structure and a positive bias voltage generated from the voltage supply is applied to a counter electrode in the electrolysis chamber to generate the H. 
     
     
         16 . The system according to  claim 8 , wherein the 3D structure is a silicon wafer.