Buried heterostructure vertical-cavity surface-emitting laser diodes using impurity induced layer disordering (IILD) via a buried impurity source

• US 6,238,944 B1
• Filed: 12/21/1999
• Issued: 05/29/2001
• Est. Priority Date: 12/21/1999
• Status: Expired due to Term

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Inventors: Floyd, Philip D.
• Primary Examiner(s): CHRISTIANSON, KEITH ALAN
• Application Number:
  US09/471,746
• Time in Patent Office: 525 Days
• Field of Search: 438/36, 438/45, 438/46, 438/47, 438/511, 438/542, 438/543, 438/550, 257/14, 257/15, 257/22, 372/43, 372/46
• US Class Current: 438/45
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: H01S 5/18308 having a special structure for lateral current or light confinement
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/1833 with more than one structure
• CPC Class Codes: H01S 5/18341 Intra-cavity contacts
• CPC Class Codes: H01S 5/18369 based on dielectric materials
• CPC Class Codes: H01S 5/2068 obtained by radiation treatment or annealing
• CPC Class Codes: H01S 5/2072 obtained by vacancy induced diffusion
• CPC Class Codes: H01S 5/3086 doping of the active layer
• CPC Class Codes: H01S 5/3414 by vacancy induced interdiffusion

Abstract

The barrier layers within a quantum well active region of a vertical cavity surface emitting laser can be silicon doped. Under thermal annealing, the silicon doped barrier layers will form disordered regions of the quantum well active region around the remaining non-disordered regions of the quantum well active region. The disordered regions of the quantum well active region will prevent diffusion of injected carriers from the non-disordered, light emitting quantum well active region.

Claims

1. A method for forming a surface emitting laser including the steps of

providing a substrate;

depositing a plurality of semiconductor layers on said substrate, said plurality of semiconductor layers including;

a lower mirror; and

an active region having a plurality of alternating quantum well layers and barrier layers, said barrier layers being impurity doped for disordering;

forming a capping mask upon a portion of the surface of said plurality of semiconductor layers;

annealing said capped plurality of semiconductor layers to cause intermixing of a first region of said disordering barrier layers and said quantum well layers under the capping mask, while leaving a second region of said disordering barrier layers and said quantum well layers to remain unintermixed;

etching said plurality of semiconductor layers to expose the edges of said plurality of semiconductor layers; and

oxidizing one of said plurality of semiconductor layers to surround and form an aperture from said non-oxidized semiconductor layer;

depositing an upper mirror; and

depositing electrodes for passing current through said second region of unintermixed quantum well layers causing light emission from said second region of unintermixed quantum well layers through said aperture through said upper mirror.

2. The method for forming a surface emitting laser as set forth in claim 1 wherein

said lower mirror is a n-doped distributed Bragg reflector, said upper mirror is an undoped dielectric mirror, said plurality of quantum well layers is undoped, and said plurality of disordering barrier layers is n-doped.

3. The method for forming a surface emitting laser as set forth in claim 1 wherein

said plurality of disordering barrier layers is n-doped only partially into the surface of each of said plurality of disordering barrier layers on one side of each of said plurality of alternating quantum well layers.

4. The method for forming a surface emitting laser as set forth in claim 1 wherein

said plurality of disordering barrier layers is n-doped only partially into the surface of each of said plurality of disordering barrier layers on both sides of each of said plurality of alternating quantum well layers.

5. A method for forming a surface emitting laser including the steps of

providing a substrate;

depositing a plurality of semiconductor layers on said substrate, said plurality of semiconductor layers including;

a lower mirror, and

an active region of a plurality of alternating quantum well layers and barrier layers, said barrier layers being impurity doped for disordering,

forming a capping mask upon a portion of the surface of said plurality of semiconductor layers;

annealing said capped plurality of semiconductor layers to cause intermixing of a first region of said disordering barrier layers and said quantum well layers under the capping mask, while leaving a second region of said disordering barrier layers and said quantum well layers to remain unintermixed;

depositing an upper mirror,

etching said plurality of semiconductor layers to expose the edges of said plurality of semiconductor layers;

oxidizing one of said plurality of semiconductor layers to surround and form an aperture from said non-oxidized semiconductor layer,

depositing electrodes for passing current through said second region of unintermixed quantum well layers causing light emission from said second region of unintermixed quantum well layers through said aperture through said upper mirror.

6. The method for forming a surface emitting laser as set forth in claim 5 wherein

said lower mirror is a n-doped distributed Bragg reflector, said upper mirror is an p-doped distributed Bragg reflector, said plurality of quantum well layers is undoped, and said plurality of disordering barrier layers is n-doped.

7. The method for forming a surface emitting laser as set forth in claim 5 wherein

said plurality of disordering barrier layers is n-doped only partially into the surface of each of said plurality of disordering barrier layers on one side of each of said plurality of alternating quantum well layers.

8. The method for forming a surface emitting laser as set forth in claim 5 wherein

said plurality of disordering barrier layers is n-doped only partially into the surface of each of said plurality of disordering barrier layers on both sides of each of said plurality of alternating quantum well layers.