Nanostructured devices

Abstract

A photovoltaic device is provided. It comprises at least two electrical contacts, p type dopants and n type dopants. It also comprises a bulk region and nanowires in an aligned array which contact the bulk region. All nanowires in the array have one predominant type of dopant, n or p, and at least a portion of the bulk region also comprises that predominant type of dopant. The portion of the bulk region comprising the predominant type of dopant typically contacts the nanowire array. The photovoltaic devices' p-n junction would then be found in the bulk region. The photovoltaic devices would commonly comprise silicon.

1 . A photovoltaic device comprising:
 a crystalline semiconductor substrate with orientation <100> comprising:
 a bottom n-doped region; 
 a top p-doped region adjacent to and in direct physical contact with the bottom n-doped region, wherein the bottom n-doped region and the top p-doped region form a p-n junction within a bulk of the crystalline semiconductor substrate, and the top p-doped region contains p-type dopant throughout its entirety; and 
 a plurality of p-doped nanowires in direct physical contact with the top p-doped region of the crystalline semiconductor substrate, the p-n junction being located at least about 30 nm from bottoms of the plurality of p-doped nanowires. 
   
     
     
         2 . The device of  claim 1 , wherein the plurality of p-doped nanowires have heights of about 0.05 um as measured from the substrate. 
     
     
         3 . The device of  claim 1 , wherein the plurality of p-doped nanowires have heights of about 0.1 um as measured from the substrate. 
     
     
         4 . The device of in  claim 1 , wherein the plurality of p-doped nanowires have heights of about 0.5 um as measured from the substrate. 
     
     
         5 . The device of  claim 1 , wherein the plurality of p-doped nanowires have diameters of about 50 nm. 
     
     
         6 . The device of  claim 1 , wherein the plurality of p-doped nanowires have diameters of about 75 nm. 
     
     
         7 . The device of  claim 1 , wherein the plurality of p-doped nanowires have diameters of about 100 nm. 
     
     
         8 . The device of  claim 1 , wherein the plurality of p-doped nanowires have diameters of about 200 nm. 
     
     
         9 . The device of  claim 1 , wherein the p-n junction is located at least about 300 nm from the bottoms of the plurality of p-doped nanowires. 
     
     
         10 . The device of  claim 1 , wherein the plurality of p-doped nanowires are disposed at an angle different from 90 degrees with respect to a surface where they have direct physical contact with the top p-doped region. 
     
     
         11 . A photovoltaic device comprising:
 a crystalline semiconductor substrate with orientation <100> comprising:
 a bottom p-doped region; 
 a top n-doped region adjacent to and in direct physical contact with the bottom p-doped region, wherein the bottom p-doped region and the top n-doped region form a p-n junction within a bulk of the crystalline semiconductor substrate, and the top n-doped region contains n-type dopant throughout its entirety; and 
 a plurality of n-doped nanowires in direct physical contact with the top n-doped region of the crystalline semiconductor substrate, the p-n junction being located at least about 30 nm from bottoms of the plurality of n-doped nanowires. 
   
     
     
         12 . The device of  claim 11 , wherein the plurality of n-doped nanowires have heights of about 0.05 um as measured from the substrate. 
     
     
         13 . The device of  claim 11 , wherein the plurality of n-doped nanowires have heights of about 0.1 um as measured from the substrate. 
     
     
         14 . The device of  claim 11 , wherein the plurality of n-doped nanowires have heights of about 0.5 um as measured from the substrate. 
     
     
         15 . The device of  claim 11 , wherein the plurality of n-doped nanowires have diameters of about 50 nm. 
     
     
         16 . The device of  claim 11 , wherein the plurality of n-doped nanowires have diameters of about 75 nm. 
     
     
         17 . The device of  claim 11 , wherein the plurality of n-doped nanowires have diameters of about 100 nm. 
     
     
         18 . The device of  claim 11 , wherein the plurality of n-doped nanowires have diameters of about 200 nm. 
     
     
         19 . The device of  claim 11 , wherein the p-n junction is located at least about 300 nm from the bottoms of the plurality of n-doped nanowires. 
     
     
         20 . The device of  claim 11 , wherein the plurality of n-doped nanowires are disposed at an angle different from 90 degrees relative to a surface where they have direct physical contact with the top n-doped region.