Tandem solar cell

Abstract

This application is related to a tandem solar cell device including a substrate, a first tunnel junction formed on the substrate, and a first p-n junction formed on the first tunnel junction wherein the first tunnel junction including a heavily doped n-type layer and an alloy layer wherein the alloy layer having an element with atomic number larger than that of Gallium.

1 . A tandem solar cell device comprising:
 a substrate;   a first tunnel junction formed on the substrate; and   a first p-n junction formed on the first tunnel junction wherein the first tunnel junction having a heavily doped n-type layer and an alloy layer wherein the alloy layer having an element with atomic number larger than that of Gallium.   
   
   
       2 . The tandem solar cell device according to  claim 1 , wherein the alloy layer further comprising a p-type impurity with high doping concentration. 
   
   
       3 . The tandem solar cell device according to  claim 1 , wherein the material of the substrate can be Silicon, Germanium, Si—Ge, GaAs or InP. 
   
   
       4 . The tandem solar cell device according to  claim 1 , further comprising a buffer layer formed between the substrate and the first tunnel junction. 
   
   
       5 . The tandem solar cell device according to  claim 4 , wherein the material of the buffer layer, the heavily doped n-type layer of the first tunnel junction, the alloy layer of the first tunnel junction and the first p-n junction contains one or more elements selected from the group consisting of Gallium, Aluminum, Indium, Arsenic, Phosphorous, Nitrogen and Silicon. 
   
   
       6 . The tandem solar cell device according to  claim 1 , wherein the element with atomic number larger than that of Gallium can be selected from the group consisting of Indium, Thallium, Antimony, Bismuth, Tin, Lead, Bismuth, Polonium, Cadmium, and Mercury. 
   
   
       7 . The tandem solar cell device according to  claim 1 , wherein the concentration of the element with atomic number larger than that of Gallium can be 1˜2%, which is equal to 3.5×10 21 ˜1.7×10 22  (1/cm 3 ). 
   
   
       8 . The tandem solar cell device according to  claim 1 , further comprising a second tunnel junction formed on the first p-n junction wherein the second tunnel junction having a heavily doped n-type layer and an alloy layer wherein the alloy layer having an element with atomic number larger than that of Gallium. 
   
   
       9 . The tandem solar cell device according to  claim 8 , further comprising a second p-n junction formed on the second tunnel junction. 
   
   
       10 . The tandem solar cell device according to  claim 8 , wherein the material of the heavily doped n-type layer of the second tunnel junction, the alloy layer of the second tunnel junction and the second p-n junction contains one or more elements selected from the group consisting of Gallium, Aluminum, Indium, Arsenic, Phosphorous, Nitrogen and Silicon. 
   
   
       11 . The tandem solar cell device according to  claim 8 , wherein the element with atomic number larger than that of Gallium can be selected from the group consisting of Indium, Thallium, Antimony, Bismuth, Tin, Lead, Bismuth, Polonium, Cadmium, and Mercury. 
   
   
       12 . The tandem solar cell device according to  claim 8 , wherein the concentration of the element with atomic number larger than that of Gallium can be 1˜2%, which is equal to 3.5×10 21 ˜1.7×10 22  (1/cm 3 ). 
   
   
       13 . The tandem solar cell device according to  claim 10 , further comprising a plurality of tunnel junction with alloy layer having an element with atomic number larger than that of Gallium and a plurality of p-n junction repeated formed on the second p-n junction separately. 
   
   
       14 . A method of manufacturing a tandem solar cell device, comprising:
 providing a substrate;   forming a tunnel junction on the substrate; and   forming a p-n junction on the tunnel junction wherein the tunnel junction having a heavily doped n-type layer and an alloy layer wherein manufacturing method of the alloy layer comprising adding a p-type impurity with high concentration and an element with atomic number larger than that of Gallium in the epitaxial process.   
   
   
       15 . The method of  claim 14 , wherein the material of the heavily doped n-type layer, the alloy layer and the p-n junction contains one or more elements selected from the group consisting of Gallium, Aluminum, Indium, Arsenic, Phosphorous, Nitrogen and Silicon. 
   
   
       16 . The method of  claim 14 , wherein the element with atomic number larger than that of Gallium can be selected from the group consisting of Indium, Thallium, Antimony, Bismuth, Tin, Lead, Bismuth, Polonium, Cadmium, and Mercury. 
   
   
       17 . The method of  claim 15 , wherein the concentration of the element with atomic number larger than that of Gallium can be 1˜2%, which is equal to 3.5×10 21 ˜1.7×10 22  (1/cm 3 ). 
   
   
       18 . The method of  claim 15 , further comprising forming a plurality of tunnel junction with alloy layer having an element with atomic number larger than that of Gallium and a plurality of p-n junction repeated on the p-n junction separately. 
   
   
       19 . The method of  claim 15 , the differences in lattice of the tunnel junction with the substrate or the p-n junction is reduced by forming the alloy layer.