Semiconductor devices with oxide coatings selectively positioned over exposed features including semiconductor material and solutions for forming the coatings

Abstract

A semiconductor device structure includes a passivation layer through which only non-semiconductor material-comprising structures are exposed. The semiconductor device structure is formed by selectively forming the passivation layer on an exposed semiconductor material-comprising surface by exposing surfaces of the semiconductor device to a liquid phase solution supersaturated in an oxide of the semiconductor material. Such a solution may include a hexafluoro acid of the semiconductor material. The oxide and acid may be present in amounts that facilitate deposition of the oxide onto exposed semiconductor material-comprising structures. The exposure may be conducted at substantially atmospheric temperature and pressure and may form a passivation layer in an abbreviated time, and without subsequent heat treatment.

1 . A semiconductor device structure, comprising: 
 a semiconductor substrate having an active surface and a back side;    at least one integrated circuit formed on the active surface, the at least one integrated circuit including electronic devices and metallization communicating with the electronic devices;    a plurality of pad sites in communication with the metallization, the plurality of pad sites comprising portions of the metallization and a solder wettable material plated to the metallization; and    an oxide passivation layer covering the back side, the oxide passivation layer applied from an aqueous solution supersaturated in oxide, the oxide passivation layer deposited at a temperature having a range of about 10° C. to about 100° C. at substantially atmospheric pressure and having a deposition time in a range of about 10 seconds to about 120 minutes, the oxide passivation layer comprising a permanent passivation layer without heat treatment.    
     
     
         2 . The semiconductor device structure of  claim 1 , wherein the semiconductor substrate comprises silicon.  
     
     
         3 . The semiconductor device structure of  claim 1 , wherein the oxide passivation layer comprises silicon dioxide.  
     
     
         4 . The semiconductor device structure of  claim 1 , further comprising a via passing through the semiconductor substrate and having its inner surfaces selectively passivated with a thin, uniform layer of silicon dioxide.  
     
     
         5 . An aqueous solution, comprising a hexafluoro acid of a semiconductor material supersaturated with an oxide of the semiconductor material, the hexafluoro acid and the oxide being present in amounts formulated to deposit the oxide onto semiconductor material-containing surfaces of a semiconductor substrate upon exposure of the semiconductor substrate to the aqueous solution without depositing the oxide onto exposed structures comprising metal.  
     
     
         6 . The aqueous solution of  claim 5 , further comprising a buffer for facilitating supersaturation of the aqueous solution with the oxide.  
     
     
         7 . The aqueous solution of  claim 6 , wherein the buffer comprises at least one of boric acid and aluminum.  
     
     
         8 . The aqueous solution of  claim 5 , wherein the hexafluoro acid and the oxide are present in amounts to promote substantially uniform deposition of the oxide at temperatures of about 10° C. to about 80° C.  
     
     
         9 . The aqueous solution of  claim 5 , wherein the hexafluoro acid and the oxide are present in amounts to promote substantially uniform deposition of the oxide at temperatures of about 20° C. to about 50° C.