VERTICAL CAVITY SURFACE EMITTING LASER, METHOD FOR FABRICATING VERTICAL CAVITY SURFACE EMITTING LASER

• US 20190067908A1
• Filed: 08/21/2018
• Published: 02/28/2019
• Est. Priority Date: 08/23/2017
• Status: Active Application

• Current Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Original Assignee: Sumitomo Electric Industries Limited (Sumitomo Corporation)
• Inventors: Onishi, Yutaka
• Granted Patent: US 10,847,950 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 21/246 with AIIIBV compounds
• CPC Class Codes: H01L 21/28575 on semiconductor bodies comprising AIIIBV compounds
• CPC Class Codes: H01L 21/308 using masks H01L21/3063, H01L21/3065 take precedence
• CPC Class Codes: H01S 5/02461 Structure or details of the laser chip to manipulate the heat flow, e.g. passive layers in the chip with a low heat conductivity
• CPC Class Codes: H01S 5/0421 characterised by the semiconducting contacting layers electrodes H01S5/0425
• CPC Class Codes: H01S 5/04257 having positive and negative electrodes on the same side of the substrate
• CPC Class Codes: H01S 5/18311 using selective oxidation
• CPC Class Codes: H01S 5/18313 by oxidizing at least one of the DBR layers
• CPC Class Codes: H01S 5/18327 Structure being part of a DBR H01S5/18391 takes precedence
• CPC Class Codes: H01S 5/18333 only above the active layer
• CPC Class Codes: H01S 5/18358 containing spacer layers to adjust the phase of the light wave in the cavity
• CPC Class Codes: H01S 5/18361 Structure of the reflectors, e.g. hybrid mirrors
• CPC Class Codes: H01S 5/18369 based on dielectric materials
• CPC Class Codes: H01S 5/18372 by native oxidation
• CPC Class Codes: H01S 5/18377 comprising layers of different kind of materials, e.g. combinations of semiconducting with dielectric or metallic layers
• CPC Class Codes: H01S 5/187 using Bragg reflection
• CPC Class Codes: H01S 5/305 characterised by the doping materials used in the laser structure
• CPC Class Codes: H01S 5/3054 p-doping
• CPC Class Codes: H01S 5/34313 with a well layer having only As as V-compound, e.g. AlGaAs, InGaAs
• CPC Class Codes: H01S 5/3432 the whole junction comprising only (AI)GaAs
• CPC Class Codes: Y10S 438/956 : Making multiple wavelength emissive device

Abstract

A vertical cavity surface emitting laser includes: a supporting base: and a post including an upper distributed Bragg reflecting region, an active layer, and a lower distributed Bragg reflecting region. The upper distributed Bragg reflecting region, the active layer, and the lower distributed Bragg reflecting region are arranged on the supporting base. The lower distributed Bragg reflecting region includes first semiconductor layers and second semiconductor layers alternately arranged. The first semiconductor layers each have a refractive index lower than that of each of the second semiconductor layers. The upper distributed Bragg reflecting region includes first layers and second layers alternately arranged. The first layers each have a group III-V compound semiconductor portion and a group III oxide portion. The group III-V compound semiconductor portion contains aluminum as a group III constituent element, and the group III oxide portion surrounds the group III-V compound semiconductor portion.

Claims

1. A vertical cavity surface emitting laser comprising:

a supporting base; and

a post including an upper distributed Bragg reflecting region, an active layer, and a lower distributed Bragg reflecting region, and the upper distributed Bragg reflecting region, the active layer, and the lower distributed Bragg reflecting region being arranged on the supporting base,

the lower distributed Bragg reflecting region including first semiconductor layers and second semiconductor layers alternately arranged,

the first semiconductor layers each having a refractive index lower than that of each of the second semiconductor layers,

the upper distributed Bragg reflecting region including first layers and second layers alternately arranged,

the first layers each having a group III-V compound semiconductor portion and a group III oxide portion,

the group III-V compound semiconductor portion containing aluminum as a group III constituent element, and

the group III oxide portion surrounding the group III-V compound semiconductor portion.

2. The vertical cavity surface emitting laser according to claim 1,

wherein the first semiconductor layers of the lower distributed Bragg reflecting region each have an aluminum composition not less than that of the group III-V compound semiconductor portion of each of the first layers of the upper distributed Bragg reflecting region.

3. The vertical cavity surface emitting laser according to claim 1,

wherein

the upper distributed Bragg reflecting region includes a current confining structure,

the current confining structure has a current aperture portion and an insulating portion,

the current aperture portion includes a group III-V compound semiconductor,

the insulating portion surrounds the current aperture portion, and

the first semiconductor layers each have an aluminum composition not less than that of the current aperture portion.

4. The vertical cavity surface emitting laser according to claim 3,

wherein the aluminum composition of each of the first semiconductor layers is larger than that of the current aperture portion.

5. A method for fabricating a vertical cavity surface emitting laser comprising:

preparing an epitaxial substrate, the epitaxial substrate including a lower semiconductor laminate for a lower distributed Bragg reflecting region, a semiconductor laminate for an active layer, and an upper semiconductor laminate for an upper distributed Bragg reflecting region;

forming a mask on the epitaxial substrate, the mask having a pattern defining a post for the vertical cavity surface emitting laser;

etching the upper semiconductor laminate and the semiconductor laminate of the epitaxial substrate with the mask to form a substrate product, and the substrate product having an upper part of the post;

exposing the upper part of the substrate product to an oxidizing atmosphere; and

after exposing the upper part of the substrate product to the oxidizing atmosphere, etching the lower semiconductor laminate to form a lower part of the post,

the upper semiconductor laminate having a semiconductor layer of III-V compound semiconductor containing aluminum as a group III constituent element,

the semiconductor layer reaching a side of the post,

exposing the upper part of the substrate product to an oxidizing atmosphere including producing a current confining structure from the semiconductor layer, and

the current confining structure having an insulating portion and a current aperture portion of the III-V compound semiconductor.