Systems and methods for nanowire growth and manufacturing

Abstract

The present invention is directed to compositions of matter, systems, and methods to manufacture nanowires. In an embodiment, a buffer layer is placed on a nanowire growth substrate and catalytic nanoparticles are added to form a catalytic-coated nanowire growth substrate. Methods to develop and use this catalytic-coated nanowire growth substrate are disclosed. In a further aspect of the invention, in an embodiment a nanowire growth system using a foil roller to manufacture nanowires is provided.

1 . A method to produce a catalytic-coated nanowire growth substrate for nanowire growth, comprising: 
 (a) depositing a buffer layer on a substrate;    (b) treating the buffer layer to enhance interactions between the buffer layer and catalyst particles; and    (c) depositing catalytic particles on a surface of the buffer layer.    
     
     
         2 . The method of  claim 1 , wherein the buffer layer provides a charged surface that attracts catalytic particles.  
     
     
         3 . The method of  claim 1 , wherein the buffer layer provides a protection layer that prevents reactions between the substrate and catalytic particles.  
     
     
         4 . The method of  claim 1 , wherein the buffer layer provides a protection layer that prevents chemical reactions between the substrate and catalytic particles.  
     
     
         5 . The method of  claim 1 , wherein the substrate comprises a semiconductor, metal, ceramic, glass or plastic.  
     
     
         6 . The method of  claim 1 , wherein the substrate is in a form of a wafer, foil, block, tube or foam.  
     
     
         7 . The method of  claim 1 , wherein the buffer layer is Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , MgO or ZnO.  
     
     
         8 . The method of  claim 1 , wherein step (a) comprises oxidation, nitridation, sputtering, spraying, dip coating, e-beam evaporation, spin coating, roll-to-roll coating, chemical vapor deposition, or plasma enhanced chemical vapor deposition to deposit the buffer layer on the substrate.  
     
     
         9 . The method of  claim 1 , wherein step (b) treating the buffer layer comprises boiling the buffer layer in water, steaming the buffer layer, treating the buffer layer with acid, treating the buffer layer with a base, or functionalizing the surface of the buffer layer.  
     
     
         10 . The method of  claim 1 , wherein step (c) comprises using charge induced self assembly, chemical functional group induced assembly, spin coating, or dip coating to deposit catalytic particles on the surface of the buffer layer.  
     
     
         11 . A catalytic-coated nanowire growth substrate for nanowire growth produced using the method of  claim 1 .  
     
     
         12 . A method to grow Si nanowires, comprising: 
 (a) depositing Al 2 O 3  on a Si substrate;    (b) treating the Al 2 O 3  coated substrate in boiling water;    (c) soaking the Al 2 O 3  coated Si substrate in a Au colloid solution; and    (d) growing nanowires on the Al 2 O 3  coated Si substrate.    
     
     
         13 . A method to grow oriented Si nanowires, comprising: 
 (a) depositing ZnO on a Si substrate;    (b) soaking the ZnO coated Si substrate produced in step (a) in an Au colloid solution; and    (c) growing oriented Si nanowires.    
     
     
         14 . The method of  claim 13 , wherein step (c) comprises introducing SiCl4 to the ZnO coated Si substrate to grow oriented Si nanowires.  
     
     
         15 . The method of  claim 13 , wherein step (a) the Si substrate is a Si <111> substrate.  
     
     
         16 . A composition of matter, comprising: 
 a nanowire growth substrate;    a buffer layer on a surface of the nanowire growth substrate; and    a layer of catalyst particles on the surface of said buffer layer.    
     
     
         17 . The composition of matter in  claim 16 , wherein said nanowire growth substrate is a semiconductor, a metal, a ceramic, a glass or a plastic.  
     
     
         18 . The composition of matter in  claim 16 , wherein said nanowire growth substrate has the form of a wafer, foil, block, tube, or foam.  
     
     
         19 . The composition of matter in  claim 16 , wherein the buffer layer provides a charged surface that attracts catalyst particles or provides a protection layer that prevents chemical reactions between the substrate and catalyst particles.  
     
     
         20 . The composition of matter in  claim 16 , wherein said buffer layer is Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , MgO or ZnO.  
     
     
         21 . The composition of matter in  claim 16 , wherein said catalyst particles comprises Au, Pt, Pd, Cu, Al, Ni, Fe, an Au alloy, a Pt alloy, a Pd alloy, a Cu alloy, an Al alloy, a Ni alloy or an Fe alloy.  
     
     
         22 . A composition of matter, comprising: 
 a nanowire growth substrate;    a buffer layer on a surface of the nanowire growth substrate;    nanowires affixed to said buffer layer; and    catalyst particles affixed to an end of said nanowires.    
     
     
         23 . The composition of matter in  claim 22 , wherein said nanowire growth substrate is a semiconductor, a metal, a ceramic, a glass or a plastic.  
     
     
         24 . The composition of matter in  claim 22 , wherein said nanowire growth substrate has the form of a wafer, foil, block, tube or foam.  
     
     
         25 . The composition of matter in  claim 22 , wherein said buffer layer is Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , MgO or ZnO.  
     
     
         26 . The composition of matter in  claim 22 , wherein said catalyst particles comprises Au, Pt, Pd, Cu, Al, Ni, Fe, an Au alloy, a Pt alloy, a Pd alloy, a Cu alloy, an Al alloy, a Ni alloy or an Fe alloy.  
     
     
         27 . The composition of matter in  claim 22 , wherein said nanowires are Si, Ge, Si x-1 Ge x , GaN, GaAs, InP, SiC, CdS, CdSe, ZnS or ZnSe.  
     
     
         28 . The composition of matter in  claim 22 , wherein said nanowires are perpendicular, at a preferred angle or randomly oriented to said nanowire growth substrate.  
     
     
         29 . The composition of matter in  claim 22 , wherein said nanowires are patterned based on various wire diameters and/or lengths.  
     
     
         30 . A composition of matter, comprising: 
 a nanowire growth substrate;    a buffer layer on a surface of the nanowire growth substrate;    nanoribbons affixed to said buffer layer; and    and catalyst particles affixed to an end of said nanoribbons.    
     
     
         31 . A nanowire growth system, comprising: 
 a roller that provides a nanowire growth substrate and for transferring nanowires through said nanowire growth system;    a catalyst spray dispenser;    a plasma cleaner;    a nanowire growth chamber; and    a nanowire harvest sonicator, wherein said roller is coupled to said catalyst spray dispenser, said plasma cleaner, said nanowire growth chamber and said nanowire harvest sonicator.    
     
     
         32 . The nanowire growth system of  claim 31 , further comprising: 
 a roller cleaner that cleans said roller;    a boiling water bath chamber that purifies said roller, wherein said roller is coupled to said roller cleaner and said boiling water bath chamber.    
     
     
         33 . The nanowire growth system of  claim 31 , further comprising a gate dielectric deposition chamber that deposits a gate dielectric on nanowires, wherein said roller is coupled to said gate dielectric deposition chamber.  
     
     
         34 . The nanowire growth system of  claim 31 , further comprising a nanowire product chamber coupled to said wire harvest sonicator for retrieval of harvested nanowires.  
     
     
         35 . The nanowire growth system of  claim 31 , further comprising a plurality of spindles that control the rate of movement of said roller.  
     
     
         36 . The nanowire growth system of  claim 31 , wherein a speed of said roller is continuous or semi-continuous.  
     
     
         37 . The nanowire growth system of  claim 31 , wherein a speed of said plurality of spindles can be adjusted based on one or more desired characteristics of a nanowire product.  
     
     
         38 . The nanowire growth system of  claim 31 , wherein said roller is metal foil.  
     
     
         39 . The nanowire growth system of  claim 38 , wherein said metal foil is an Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , MgO, or ZnO foil.  
     
     
         40 . The nanowire growth system of  claim 38 , wherein said metal foil is a nickel foil, steel foil, stainless steel foil, or titanium foil.  
     
     
         41 . The nanowire growth system of  claim 31 , wherein said catalyst spray dispenser is an Au colloid spray dispenser.  
     
     
         42 . The nanowire growth system of  claim 31 , wherein said nanowire growth chamber is a low pressure chemical vapor deposition nanowire growth chamber or a pure gas phase nanowire growth chamber.  
     
     
         43 . The nanowire growth system of  claim 31 , wherein concentrations of process gases are varied within said nanowire growth chamber to produce nanowires with particular characteristics.  
     
     
         44 . A method for producing nanowires using a nanowire growth system, comprising: 
 (a) spraying a catalyst on a roller of the nanowire growth system;    (b) advancing the roller to a plasma cleaner;    (c) cleaning the catalyst within the plasma cleaner;    (d) advancing the roller to a nanowire growth chamber;    (e) growing nanowires within the nanowire growth chamber;    (f) advancing the roller to a wire harvest sonicator; and    (g) harvesting nanowires.    
     
     
         45 . The method of  claim 44 , further comprising: 
 (h) advancing the roller to a roller cleaner;    (i) cleaning the roller within the roller cleaner;    (j) advancing the roller to a boiling water bath chamber; and    (k) recleaning the roller in the boiling water bath chamber.    
     
     
         46 . The method of  claim 44 , further comprising between (e) and (f): 
 (h) advancing the roller to a gate dielectric deposition chamber; and    (i) depositing gate dielectrics on nanowires.    
     
     
         47 . The method of  claim 44 , wherein said roller is a metal foil.  
     
     
         48 . The method of  claim 47 , wherein said metal foil is an Al 2 O 3 , SiO 2 , TiO 2 , ZrO 2 , MgO, or ZnO foil.  
     
     
         49 . The method of  claim 47 , wherein said metal foil is a stainless steel foil, a steel foil, a titanium foil or a nickel foil.  
     
     
         50 . The method of  claim 44 , wherein the method is continuous or semi-continuous.