Method and system for the localized deposit of metal on a surface

Abstract

The present disclosure is directed to a method and system for the localized deposition of a metal layer on a surface. The method involves introducing at least two gaseous reactants to a substrate surface that is locally heated by a laser. The surface is heated to a temperature at which the gaseous reactants undergo a reaction that results in metal crystal growth on the substrate surface. The reaction is maintained for a desired period of time and under desired conditions to produce a localized deposit of a metal layer on the heated zone of the substrate. In some embodiments, the gas outlets and the laser may be moved in a controlled manner so that a metal layer may be deposited in a desired pattern on the substrate surface.

What is claimed: 
     
         1 . A method for the localized deposition of a metal layer comprising:
 (a) introducing
 a first gaseous reactant, the first gaseous reactant comprising a metal-containing precursor, and 
 a second gaseous reactant to a surface of a substrate, wherein the first and second gaseous reactants are introduced to the surface of the substrate through one or more gas outlets; and 
   (b) directing a laser against a location on the substrate surface that is adjacent to the one or more gas outlets, thereby heating a zone of the surface to a temperature at which the first and second gaseous reactants react, such that a metal layer is deposited on the heated zone of the substrate surface.   
     
     
         2 . The method of  claim 1 , further comprising:
 (c) moving the one or more gas outlets and the laser in a controlled manner so as to deposit the metal layer in a desired pattern on the substrate surface.   
     
     
         3 . The method of  claim 2 , wherein the substrate comprises a pattern and the one or more gas outlets and the laser follow the pattern. 
     
     
         4 . The method of  claim 1 , wherein the one or more gas outlets are configured to introduce a mixture of the first and second gaseous reactants substantially evenly across the heated zone of the surface. 
     
     
         5 . The method of  claim 1 , wherein the first and second gaseous reactants are introduced through a single outlet, the diameter of the outlet being less than the diameter of the heated zone. 
     
     
         6 . The method of  claim 5 , wherein the outlet has a diameter that is between about 50% and about 95% of the diameter of the heated zone. 
     
     
         7 . The method of  claim 1 , in which the first gaseous reactant and the second gaseous reactant are introduced through separate gas outlets. 
     
     
         8 . The method of  claim 1 , wherein the heated zone has a diameter that is less than 10 mm. 
     
     
         9 . The method of  claim 1 , wherein the heated zone has a diameter that is less than 5 mm. 
     
     
         10 . The method of  claim 1 , wherein the one or more gas outlets are positioned between about 3 mm and about 20 mm above the substrate surface. 
     
     
         11 . The method of  claim 10 , wherein the one or more gas outlets are positioned between about 5 mm and about 10 mm above the substrate surface. 
     
     
         12 . The method of  claim 1 , wherein the metal of the metal-containing precursor is a transition metal. 
     
     
         13 . The method of  claim 1 , wherein the metal-containing precursor has the formula MX n , in which:
 M is a transition metal,   X is a halogen, and   n is an integer selected from the group consisting of 5 and 6;   
       and the second gaseous reactant is H 2 . 
     
     
         14 . The method of  claim 13 , in which the transition metal is selected from the group consisting of tungsten (W), molybdenum (Mo), tantalum (Ta), titanium (Ti), rhenium (Re), niobium (Nb), nickel (Ni), and hafnium (Hf); and the halogen is selected from the group consisting of fluorine, chlorine, and bromine. 
     
     
         15 . The method of  claim 13 , in which the metal-containing precursor is selected from the group consisting of tungsten hexafluoride and tungsten hexachloride. 
     
     
         16 . The method of  claim 1 , wherein the deposited metal layer is monocrystalline. 
     
     
         17 . The method of  claim 16 , wherein the deposited metal layer is monocrystalline tungsten. 
     
     
         18 . The method of  claim 1 , in which the substrate is a silicon wafer. 
     
     
         19 . A system for the localized deposition of a metal layer according to the method of  claim 1 , comprising:
 (a) a substrate, the substrate having a surface;   (b) one or more gas outlets, the one or more gas outlets being in communication with at least a first gaseous reactant and a second gaseous reactant, and the one or more gas outlets being positioned adjacent to a portion of the substrate surface; and   (c) a laser, the laser being configured to direct its output against the portion of the substrate surface in order to heat a zone of the substrate surface to a desired temperature.   
     
     
         20 . The system of  claim 19 , wherein both the one or more gas outlets and the laser are configured to travel along the substrate surface in a controlled manner.