Patent ID: 11967800
Assignee: TRUELIGHT CORPORATION
Field: Optics (Instruments)
Classification: CPC H | IPC H

Claim 5:
6. A method for fabricating a surface emitting laser with hybrid grating structure, said method comprising:
applying a semiconductor epitaxy process to form a semiconductor-laminated structure on a semiconductor substrate; the semiconductor-laminated structure generating a laser beam with a laser wavelength upon receiving an electric current; the semiconductor-laminated structure emitting the laser beam from at least one light-emitting surface located at a top surface of the semiconductor-laminated structure;
applying an e-beam writer process and a nano imprint process to form a grating layer on the semiconductor-laminated structure; the grating layer comprising a plurality of micro-grating structures arranged at least in a first horizontal direction;
applying an epitaxy process and a yellow-light process to form an upper cladding layer and a contact layer on the grating layer;
wherein, the grating layer is divided into at least one first grating region and at least one second grating region at least along the first horizontal direction, each of the first and second grating regions contains a plurality of the micro-grating structures respectively;
wherein, the grating period of the micro-grating structures in each said first grating region is in accordance with the following mathematical formula:, ∧
   
    =
    
     m
     ⁢
     
      λ
      
       2
       ⁢
       
        n
        eff
       
      
     
    
   
  
  ;
 

 in addition, the grating period of the micro-grating structures in each said second grating region is in accordance with the following mathematical formula:, ∧
   
    =
    
     O
     ⁢
     
      λ
      
       2
       *
       
        n
        eff
       
      
     
    
   
  
  ;
 

 wherein, ∧ is a length of grating period; λ is a wavelength of the laser light; neff is an the equivalent refractive index of semiconductor waveguide; both m and o are integrals; m is not equal to o; and o is an even multiple of m;
wherein, the at least one light-emitting surface is defined by the at least one second grating region;
wherein the grating layer also has a plurality of micro-grating structures along a second horizontal direction; the second horizontal direction is perpendicular to the first horizontal direction, and both the second horizontal direction and the first horizontal direction are perpendicular to the emitting direction of the laser light; the grating layer is also divided into at least one first grating region and at least one second grating region along the second horizontal direction, each of the first and second grating regions along the second horizontal direction also contains a plurality of said micro-grating structures respectively; when viewed downwardly from the top surface of the semiconductor-laminated structure, the micro-grating structures are arranged in a dot-like array on the grating layer; in addition, the at least one second grating region in the first horizontal direction and the at least one second grating region in the second horizontal direction cooperate to define said at least one light-emitting surface;
wherein the top surface of the semiconductor-laminated structure includes a plurality of individual said light-emitting surfaces separated from each other and arranged in an array-format; the grating layer is provided with the second grating region at each said light-emitting surface, no matter in the first horizontal direction or the second horizontal direction; in addition, except for the light-emitting surfaces, other portions of the grating layer are all provided with the first grating region regardless of whether it is in the first horizontal direction or the second horizontal direction; such that, several individually separated said light-emitting surfaces capable of emitting laser light are arranged in said array-format on the top surface of the semiconductor-laminated structure of the surface emitting laser.