Surface-emission laser diode and fabrication process thereof

• US 8,743,924 B2
• Filed: 02/11/2013
• Issued: 06/03/2014
• Est. Priority Date: 06/11/2004
• Status: Active Grant

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Sato, Shunichi, Itoh, Akihiro, Jikutani, Naoto
• Primary Examiner(s): Park, Kinam
• Application Number:
  US13/764,167
• Publication Number:
  US 20140064313A1
• Time in Patent Office: 477 Days
• Field of Search: 372/50.124, 372/45.01, 372/45.011, 372/50.11
• US Class Current: 372/50.124
• CPC Class Codes: H01S 5/02251 using optical fibres
• CPC Class Codes: H01S 5/04256 characterised by the configuration
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/18347 Mesa comprising active layer
• CPC Class Codes: H01S 5/18383 with periodic active regions at nodes or maxima of light intensity
• CPC Class Codes: H01S 5/2205 comprising special burying or current confinement layers
• CPC Class Codes: H01S 5/343 in AIIIBV compounds, e.g. AlGaAs-laser , InP-based laser
• CPC Class Codes: H01S 5/423 having a vertical cavity

Abstract

In a surface-emission laser diode, there is provided, between an active layer and a semiconductor layer that contains Al, Ga and As as major components, a semiconductor layer containing Al, In and P as major components such that the semiconductor layer containing Al, In and P as major components is provided adjacent to the semiconductor layer that contains Al, Ga and As as major components. Further, an interface between the semiconductor layer containing Al, Ga and As as major components and the semiconductor layer containing Al, In and P as major components is coincident to a location of a node of electric field strength distribution.

Claims

1. A surface-emission laser diode, comprising:

a GaAs substrate;

a cavity region formed over said GaAs substrate, said cavity region including at least one quantum well active layer producing a laser light and barrier layers; and

an upper reflector and a lower reflector provided at a top part and a bottom part of said cavity region over said GaAs substrate,

said upper reflector and/or said lower reflector including a semiconductor Bragg reflector,

at least a part of said semiconductor distributed Bragg reflector comprising a semiconductor layer containing Al, Ga and As as major components,

wherein there is provided, between said active layer and said semiconductor layer that contains Al, Ga and As as major components, a semiconductor layer containing Al, In and P as major components such that said semiconductor layer containing Al, In and P as major components is provided adjacent to said semiconductor layer that contains Al, Ga and As as major components,

an interface between said semiconductor layer containing Al, Ga and As as major components and said semiconductor layer containing Al, In and P as major components being formed coincident to a location of a node of electric field strength distribution.

2. The surface-emission laser diode as claimed in claim 1, characterized in that said semiconductor layer containing Al, In and P as major components comprises (Al_aGa_1-a)_bIn_1-bP (0<

a=1, 0≦

b≦

1).

3. The surface-emission laser diode as claimed in claim 1, characterized in that

there is provided a spacer layer between said active layer and said upper reflector and/or lower reflector, a part of said spacer layer comprising an AlGaInP layer,

said quantum well active layer comprises Ga_cIn_1-cP_dAd_1-d (0≦

c≦

1, 0≦

d≦

1), and

said barrier layer comprises Ga_eIn_1-eP_fAs_1-f (0≦

e≦

1, 0≦

f≦

1).

4. The surface-emission laser diode as claimed in claim 3, characterized in that said quantum well active layer has a compressive strain.

5. The surface-emission laser diode as claimed in claim 4, characterized in that said barrier layer has a tensile strain.