Apparatus and method for producing solar cells

Abstract

A method and apparatus for forming a solar cell. The apparatus includes a housing defining a vacuum chamber and a rotatable substrate apparatus configured to hold a plurality of substrates on a plurality of surfaces. A first sputtering source is configured to deposit a plurality of absorber layer atoms of a first type over at least a portion of a surface of each one of the plurality of substrates. An evaporation source is configured to deposit a plurality of absorber layer atoms of a second type over at least a portion of the surface of each one of the plurality of substrates.

What we claim is: 
     
         1 . An apparatus for forming a solar cell, comprising:
 a housing defining a vacuum chamber;   a rotatable substrate apparatus configured to hold a plurality of substrates on a plurality of surfaces;   a first sputtering source configured to deposit a plurality of absorber layer atoms of a first type over at least a portion of a surface of each one of the plurality of substrates; and   an evaporation source configured to deposit a plurality of absorber layer atoms of a second type over at least a portion of the surface of each one of the plurality of substrates.   
     
     
         2 . The apparatus of  claim 1 , wherein each of the plurality of surfaces is disposed facing an interior surface of the vacuum chamber. 
     
     
         3 . The apparatus of  claim 1 , further comprising:
 a first isolation source configured to isolate the evaporation source from the first sputtering source.   
     
     
         4 . The apparatus of  claim 3 ,wherein the first isolation source comprises one or more of an isolation pump. 
     
     
         5 . The apparatus of  claim 3 , wherein the first isolation source comprises:
 a vacuum pump disposed within a first subchamber of the vacuum chamber-to maintain the pressure in the first subchamber lower than the pressure in the vacuum chamber outside of the first subchamber.   
     
     
         6 . The apparatus of  claim 1 , wherein the evaporation source is disposed in the first subchamber. 
     
     
         7 . The apparatus of  claim 1 , further comprising:
 a heater apparatus configured to heat the plurality of substrates, wherein the heater apparatus has a shape that is substantially conformal with the shape of the substrate apparatus.   
     
     
         8 . The apparatus of  claim 1 , further comprising:
 a second sputtering source configured to deposit a plurality of absorber layer atoms of a third type over at least a portion of the surface of each one of the plurality of substrates.   
     
     
         9 . The apparatus of  claim 1 , further comprising:
 an isolation baffle disposed about the evaporation source.   
     
     
         10 . The apparatus of  claim 8 , further comprising:
 a first isolation pump disposed between the evaporation source and the second sputtering source; and wherein the first isolation source is disposed between the evaporation source and the first sputtering source.   
     
     
         11 . The apparatus of  claim 8 , wherein the first type comprises copper, the second type comprises selenium and the third type comprises indium. 
     
     
         12 . The apparatus of  claim 11 , wherein the first sputtering source is configured to deposit a plurality of absorber layer atoms of a first type and a fourth type over at least a portion of the surface of each one of the plurality of substrates, and wherein the fourth type is gallium. 
     
     
         13 . The apparatus of  claim 1 , wherein each of the plurality of surfaces of the substrate apparatus are disposed at a predetermined tilt angle relative to an interior surface of the vacuum chamber. 
     
     
         14 . A method of forming a solar cell, comprising:
 disposing a plurality of substrates about a plurality of surfaces of a substrate apparatus that is operatively coupled to rotate within a vacuum chamber;   rotating the substrate apparatus;   forming an absorber monolayer over a surface of each one of the plurality of substrates, the step of forming comprising:   depositing a plurality of absorber layer atoms of a first type over at least a portion of the surface of each one of the plurality of substrates;   depositing a plurality of absorber layer atoms of a second type over at least a portion of the surface;   depositing a plurality of absorber layer atoms of a third type deposit over at least a portion of the surface of each one of the plurality of substrates; and   reacting the plurality of absorber layer atoms of the first and third types with the plurality of absorber layer atoms of the second type to form the absorber monolayer.   
     
     
         15 . The method of  claim 14 , wherein the absorber layer atoms of the first type are deposited using a first sputtering source, the absorber layer atoms of the second type are deposited using an evaporation source, and the absorber layer atoms of the third type are deposited using a second sputtering source. 
     
     
         16 . The method of  claim 15 , further comprising:
 evacuating absorber layer atoms of the second type from the vacuum chamber to prevent contamination of the first and second sputtering sources using a first isolation pump.   
     
     
         17 . The method of  claim 14 , wherein the first type comprises copper, the second type comprises selenium and the third type comprises indium. 
     
     
         18 . An apparatus for forming a solar cell, comprising:
 a housing defining a vacuum chamber;   a rotatable substrate apparatus configured to hold a plurality of substrates on a plurality of surfaces;   a first sputtering source configured to deposit a plurality of absorber layer atoms of a first type over at least a portion of the surface of each one of the plurality of substrates;   an evaporation source disposed in a first subchamber of the vacuum chamber and configured to deposit a plurality of absorber layer atoms of a second type over at least a portion of the surface of each one of the plurality of substrates; and   a second sputtering source configured to deposit a plurality of absorber layer atoms of a third type over at least a portion of the surface of each one of the plurality of substrates.   
     
     
         19 . The apparatus of  claim 18 , further comprising:
 a third sputtering source disposed in a first subchamber of the vacuum chamber and configured to deposit a buffer layer over the surface of each one of the plurality of substrates.   
     
     
         20 . The apparatus of  claim 18 , further comprising:
 an evacuation source configured to evacuate atoms from the vacuum chamber to prevent contamination of the first and second sputtering sources.