Dopant diffusion blocking for optoelectronic devices using InAIAs or InGaAIAs

Abstract

A method for decreasing the diffusion of dopant atoms in the active region, as well as the interdiffusion of different types of dopant atoms among adjacent doped regions, of optoelectronic devices is disclosed. The method of the present invention employs a plurality of InAlAs and/or InGaAlAs layers to avoid the direct contact between the dopant atoms and the active region, and between the dopant atoms in adjacent blocking structures of optoelectronic devices. A semi-insulating buried ridge structure, as well as a ridge structure, in which the interdiffusion of different types of dopant atoms is suppressed are also disclosed.

1 - 29 . (Canceled)  
     
     
         30 . A method for forming a semiconductor laser comprising the steps of: 
 forming a plurality of stacked layers over a substrate of a first type conductivity, at least one of said layers being an active region and at least another one of said layers being a dopant blocking layer, said dopant blocking layer comprising a material selected from the group consisting of InAlAs and InGaAlAs; and    etching said plurality of stacked layers and said substrate to form a mesa structure on said substrate.    
     
     
         31 . The method of  claim 30  further comprising the steps of forming a first current blocking layer at two sides of said mesa structure, forming a second current blocking layer of a first type conductivity over said first current blocking layer, and forming a cladding layer of a second type conductivity over said mesa and said second current blocking layer.  
     
     
         32 . The method of  claim 30 , wherein said first type conductivity is n-type and said second type conductivity is p-type.  
     
     
         33 . The method of  claim 30 , wherein said first type conductivity is p-type and said second type conductivity is n-type.  
     
     
         34 . The method of  claim 30  further comprising the step of forming a plurality of current blocking layers at said two sides of said mesa structure.  
     
     
         35 . The method of  claim 30 , wherein said dopant blocking layer region, said second cladding layer being formed on top of and in contact with said dopant blocking layer.  
     
     
         36 . The method of  claim 35 , wherein said second cladding layer is grown selectively by metal organic vapor phase epitaxy.  
     
     
         37 . The method of  claim 35 , wherein said second cladding layer is of a second type conductivity.  
     
     
         38 . The method of  claim 35  further comprising the step of doping said second cladding layer.  
     
     
         39 . The method of  claim 30 , wherein said dopant blocking layer is epitaxially grown.  
     
     
         40 . The method of  claim 30 , wherein said dopant blocking layer is grown selectively by metal organic vapor phase epitaxy.  
     
     
         41 . The method of  claim 30 , wherein said dopant blocking layer is grown to a thickness in the range of about 300 to 800 Angstroms.  
     
     
         42 . The method of  claim 30 , wherein said active region includes a layer capable of emitting light when excited.  
     
     
         43 . The method of  claim 30 , wherein said active region includes a layer capable of absorbing light.  
     
     
         44 . The method of  claim 30 , wherein said active region includes a layer capable of modulating light.  
     
     
         45 . The method of  claim 30 , wherein said active region includes a layer capable of amplifying light.  
     
     
         46 . The method of  claim 30 , wherein said dopant blocking layer comprises at least one InAlAs layer.  
     
     
         47 . The method of  claim 30 , wherein said dopant blocking layer comprises at least one InGaAlAs layer.  
     
     
         48 . The method of  claim 30 , wherein said dopant blocking layer comprises at least one layer of InAlAs and at least one layer of InGaAlAs.  
     
     
         49 - 104 . (Canceled)