Semiconductor optical device and method for manufacturing the same

Abstract

A method for manufacturing a semiconductor optical device includes forming an epitaxial structure containing at least an active layer which can emit light, of a III-V group semiconductor material; forming an insulating layer over the epitaxial structure, which prevents the V group element from escaping from the epitaxial structure during heat treatment; heat treating the epitaxial structure at at least 800 degrees C.; and removing the insulating layer, thereby enhancing the reliability of the device.

1 . A method of manufacturing a semiconductor optical device comprising: 
 growing an epitaxial structure containing at least an active layer which can emit light, of a III-V semiconductor material including a group V element;    forming an insulating layer over the epitaxial structure, which can prevent the V group element from escaping during heat treatment;    heat treating the epitaxial structure at a temperature of at least 800 degrees C.;    removing the insulating layer.    
     
     
         2 . The method of manufacturing a semiconductor optical device according to  claim 1  comprising performing a photoluminescence measurement after the heat treating.  
     
     
         3 . A semiconductor optical device comprising an epitaxial structure of a III-V group semiconductor material, containing at least an active layer which can emit light, wherein composition of the epitaxial structure continuously changes near an interface.  
     
     
         4 . The semiconductor optical device according to  claim 3 , wherein a photoluminescence wavelength of the optical device is blue-shifted, as compared to a semiconductor optical device which has an active layer with the same composition as said active layer and an epitaxial structure with a composition that changes stepwise near the interface.  
     
     
         5 . The semiconductor optical device according to  claim 4 , wherein the photoluminescence wavelength is blue-shifted by at least 20 meV.  
     
     
         6 . The semiconductor optical device according to  claim 3 , wherein distortion of the epitaxial structure is reduced compared to a semiconductor optical device which has an active layer with the same composition as said active layer and an epitaxial structure with a composition changing stepwise near the interface.