Substrates and methods for fabricating the same

Abstract

An embodiment of the invention provides a substrate. The substrate comprises a single crystal substrate. An epitaxial buffer film is on the single crystal substrate. An epitaxial ZnGa 2 O 4 is on the epitaxial buffer film.

1 - 9 . (canceled) 
   
   
       10 . A method for fabricating a substrate, comprising:
 providing a single crystal substrate;   epitaxially growing a buffer film on the single crystal substrate; and   epitaxially growing a ZnGa 2 O 4  film on the buffer film.   
   
   
       11 . The method for fabricating the substrate as claimed in  claim 10 , further comprising epitaxially growing a stress buffer film between the buffer film and the ZnGa 2 O 4  film. 
   
   
       12 . The method for fabricating the substrate as claimed in  claim 10 , wherein the buffer film comprises rock salt TiN. 
   
   
       13 . The method for fabricating the substrate as claimed in  claim 10 , wherein the single crystal substrate comprises Si, MgO or sapphire. 
   
   
       14 . The method for fabricating the substrate as claimed in  claim 11 , wherein the stress buffer film comprises Zn 2 TiO 4 . 
   
   
       15 . The method for fabricating the substrate as claimed in  claim 10 , wherein the epitaxial growth of the ZnGa 2 O 4  film on the buffer film comprises depositing an amorphous ZnGa 2 O 4  film on the buffer film. 
   
   
       16 . The method for fabricating the substrate as claimed in  claim 10 , wherein the epitaxial growth of the ZnGa 2 O 4  film on the buffer film comprises performing an annealing process. 
   
   
       17 . The method for fabricating the substrate as claimed in  claim 16 , wherein the annealing process is performed at a temperature ranging from 400° C. to 700° C. 
   
   
       18 . The method for fabricating the substrate as claimed in  claim 16 , wherein the annealing process comprises a rapid thermal annealing process. 
   
   
       19 . The method for fabricating the substrate as claimed in  claim 15 , wherein the amorphous ZnGa 2 O 4  film is deposited on the buffer film by using DC sputtering. 
   
   
       20 . The method for fabricating the substrate as claimed in  claim 10 , wherein the epitaxial growth of the buffer film on the single substrate is performed by reactive DC sputtering or pulsed-laser deposition. 
   
   
       21 . The method for fabricating the substrate as claimed in  claim 10 , wherein the epitaxial growth of the stress buffer film between the buffer film the ZnGa2O4 film comprises reacting the buffer film with Zn in a furnace containing O 2  and Ar gas. 
   
   
       22 . The method for fabricating the substrate as claimed in  claim 10 , wherein the epitaxial growth of the ZnGa 2 O 4  film on the buffer film comprises heating the substrate and the buffer film to a temperature of about 200° C. to 1000° C.