Apparatus for forming copper indium gallium chalcogenide layers

Abstract

A multilayer structure to form absorber layers for solar cells. The multilayer structure includes a base comprising a contact layer on a substrate layer, a first layer on the contact layer, and a metallic layer on the first layer. The first layer includes an indium-gallium-selenide film and the gallium to indium molar ratio of the indium-gallium-selenide film is in the range of 0 to 0.8. The metallic layer includes gallium and indium without selenium. Additional selenium is deposited onto the metallic layer before annealing the structure for forming an absorber.

1 . A multilayer structure to form a Group IBIIIAVIA compound absorber for solar cells, comprising:
 a base comprising a substrate;   a first layer formed on the base, the first layer comprising an indium-gallium-selenide film wherein the gallium to (gallium plus indium) molar ratio of the indium-gallium-selenide film is in the range of 0 to 0.8; and   a metallic layer formed on the first layer, the metallic layer comprising gallium and indium without a Group VIA material, wherein the first layer and the metallic layer are distinct layers with no substantial reaction therebetween.   
     
     
         2 . The multilayer structure of  claim 1  wherein indium and gallium in the metallic layer form a stack comprising at least one indium film and at least one gallium film. 
     
     
         3 . The multilayer structure of  claim 1 , wherein the first layer further comprises a copper film, and wherein the indium-gallium-selenide film and the copper film are distinct films with no substantial reaction therebetween. 
     
     
         4 . The multilayer structure of  claim 3  wherein the copper film is interposed between the base and the indium-gallium-selenide film. 
     
     
         5 . The multilayer structure of  claim 3  wherein the metallic layer further comprises copper. 
     
     
         6 . The multilayer structure of  claim 5  wherein a ratio of number of moles of gallium to the total number of moles of gallium and indium in the metal layer is in the range of 0.2-0.3.9. 
     
     
         7 . The multilayer structure of  claim 3  wherein a ratio of number of moles of gallium to the total number of moles of gallium and indium in the metal layer is in the range of 0.2-0.3.8. 
     
     
         8 . The multilayer structure of  claim 3  wherein the copper film is interposed between the indium-gallium-selenide film and the metallic layer. 
     
     
         9 . The multilayer structure of  claim 8  wherein a ratio of number of moles of gallium to the total number of moles of gallium and indium in the metal layer is in the range of 0.2-0.3. 
     
     
         10 . The multilayer structure of  claim 2  wherein the metallic layer further comprises metallic stack including at least one copper film, wherein the gallium and indium without the Group VIA material form one metal layer different than the at least one copper film. 
     
     
         11 . The multilayer structure of  claim 10  wherein a ratio of number of moles of gallium to the total number of moles of gallium and indium in the metal layer is in the range of 0.2-0.3. 
     
     
         12 . The multilayer structure of  claim 1  wherein the metallic layer further comprises copper. 
     
     
         13 . The multilayer structure of  claim 1  wherein a ratio of number of moles of gallium to the total number of moles of gallium and indium in the metal layer is in the range of 0.2-0.3. 
     
     
         14 - 20 . (canceled)