Growth of reduced dislocation density non-polar gallium nitride

Abstract

Lateral epitaxial overgrowth (LEO) of non-polar gallium nitride (GaN) films results in significantly reduced defect density.

1 . A method of growing a semiconductor film, comprising:
 performing a lateral epitaxial overgrowth of a gallium nitride (GaN) film on a substrate, wherein the GaN film has a top surface that is planar and non-polar.   
     
     
         2 . The method of  claim 1 , wherein the substrate is a patterned substrate, and the GaN film nucleates only on exposed portions of the patterned substrate. 
     
     
         3 . The method of  claim 2 , wherein the GaN film grows vertically from the exposed portions of the patterned substrate and spreads laterally above the patterned substrate resulting in the top surface that is planar and non-polar. 
     
     
         4 . The method of  claim 3 , wherein the GaN film is a coalesced film have lower dislocation and stacking fault densities in its overgrown regions due to blocking of dislocations by a mask or bending of dislocations through a transition from vertical to lateral growth. 
     
     
         5 . The method of  claim 2 , wherein the patterned substrate is a substrate with a mask thereon, and the mask contains apertures or stripes therein that expose portions of the substrate. 
     
     
         6 . The method of  claim 5 , wherein the patterned substrate is an r-plane sapphire (Al 2 O 3 ) substrate. 
     
     
         7 . The method of  claim 2 , wherein the lateral epitaxial growth of the GaN film on the patterned substrate results in a defect reduction and a film quality improvement in the GaN film as compared to a non-polar GaN film grown directly on a uniform substrate. 
     
     
         8 . The method of  claim 1 , wherein the substrate is foreign substrate and the lateral epitaxial growth of the GaN film is performed directly off of the foreign substrate. 
     
     
         9 . The method of  claim 1 , wherein the lateral epitaxial overgrowth is performed using hydride vapor phase epitaxy (HVPE). 
     
     
         10 . A semiconductor film grown using the method of  claim 1 . 
     
     
         11 . A semiconductor film, comprising:
 a lateral epitaxial overgrowth of a gallium nitride (GaN) film on a substrate, wherein the GaN film has a top surface that is planar and non-polar.   
     
     
         12 . The film of  claim 11 , wherein the substrate is a patterned substrate, and the GaN film nucleates only on exposed portions of the patterned substrate. 
     
     
         13 . The film of  claim 12 , wherein the GaN film grows vertically from the exposed portions of the patterned substrate and spreads laterally above the patterned substrate resulting in the top surface that is planar and non-polar. 
     
     
         14 . The film of  claim 13 , wherein the GaN film is a coalesced film have lower dislocation and stacking fault densities in its overgrown regions due to blocking of dislocations by a mask or bending of dislocations through a transition from vertical to lateral growth. 
     
     
         15 . The film of  claim 12 , wherein the patterned substrate is a substrate with a mask thereon, and the mask contains apertures or stripes therein that expose portions of the substrate. 
     
     
         16 . The film of  claim 15 , wherein the patterned substrate is an r-plane sapphire (Al 2 O 3 ) substrate. 
     
     
         17 . The film of  claim 12 , wherein the lateral epitaxial growth of the GaN film on the patterned substrate results in a defect reduction and a film quality improvement in the GaN film as compared to a non-polar GaN film grown directly on a uniform substrate. 
     
     
         18 . The film of  claim 11 , wherein the substrate is foreign substrate and the lateral epitaxial growth of the GaN film is performed directly off of the foreign substrate.