METHOD FOR GROWING BETA-Ga2O3-BASED SINGLE CRYSTAL FILM, AND CRYSTALLINE LAYERED STRUCTURE

Abstract

As one embodiment, the present invention provides a method for growing a β-Ga 2 O 3 -based single crystal film by using HVPE method. The method includes a step of exposing a Ga 2 O 3 -based substrate to a gallium chloride-based gas and an oxygen-including gas, and growing a β-Ga 2 O 3 -based single crystal film on a principal surface of the Ga 2 O 3 -based substrate at a growth temperature of not lower than 900° C.

1 . A method for growing a β-Ga 2 O 3 -based single crystal film by HYPE method, comprising a step of exposing a Ga 2 O 3 -based substrate to a gallium chloride-based gas and an oxygen-including gas and growing a β-Ga 2 O 3 -based single crystal film on a principal surface of the Ga 2 O 3 -based substrate at a growth temperature of not lower than 900° C. 
     
     
         2 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein the gallium chloride-based gas is produced by reacting a gallium source with a Cl-including gas comprising a Cl 2  gas or an HCl gas. 
     
     
         3 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein in the gallium chloride-based gas a GaCl gas has a highest partial pressure ratio. 
     
     
         4 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein the oxygen-including gas comprises an O 2  gas. 
     
     
         5 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein the Cl-including gas comprises a Cl 2  gas. 
     
     
         6 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein a ratio of a supplied partial pressure of the oxygen-including gas to a supplied partial pressure of the gallium chloride-based gas when growing the β-Ga 2 O 3 -based single crystal film is not more than 0.5. 
     
     
         7 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein the principal surface of the Ga 2 O 3 -based substrate has a plane orientation of (010), (−01), (001) or (101). 
     
     
         8 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 1 , wherein the gallium chloride-based gas is produced at an atmosphere temperature of not less than 300° C. 
     
     
         9 . A crystalline layered structure, comprising:
 a Ga 2 O 3 -based substrate; and   a β-Ga 2 O 3 -based single crystal film that is formed on a principal surface of the Ga 2 O 3 -based substrate by epitaxial crystal growth and includes Cl.   
     
     
         10 . The crystalline layered structure according to  claim 9 , wherein a Cl concentration in the β-Ga 2 O 3 -based single crystal film is not more than 5×10 16  atoms/cm 3 . 
     
     
         11 . The crystalline layered structure according to  claim 9 , wherein the β-Ga 2 O 3 -based single crystal film comprises a β-Ga 2 O 3  crystal film. 
     
     
         12 . The crystalline layered structure according to  claim 11 , wherein a residual carrier concentration in the β-Ga 2 O 3 -based single crystal film is not more than 3×10 15  atoms/cm 3 . 
     
     
         13 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein in the gallium chloride-based gas a GaCl gas has a highest partial pressure ratio. 
     
     
         14 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein the oxygen-including gas comprises an O 2  gas. 
     
     
         15 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein a ratio of a supplied partial pressure of the oxygen-including gas to a supplied partial pressure of the gallium chloride-based gas when growing the β-Ga 2 O 3 -based single crystal film is not more than 0.5. 
     
     
         16 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein the principal surface of the Ga 2 O 3 -based substrate has a plane orientation of (010), (−201), (001) or (101). 
     
     
         17 . The method for growing a β-Ga 2 O 3 -based single crystal film according to  claim 2 , wherein the gallium chloride-based gas is produced at an atmosphere temperature of not less than 300° C. 
     
     
         18 . The crystalline layered structure according to  claim 10 , wherein the β-Ga 2 O 3 -based single crystal film comprises a β-Ga 2 O 3  crystal film.