Finisar Corporation

Hoki Kwon

Tzu-Yu Wang

Jin Kwang Kim

Gyoungwon Park

Jae-Hyun Ryou

Distributed Bragg reflector (DBR) with reduced DX centers. A DBR includes an AlAs region. The AlAs region includes essentially homogeneous AlAs. The DBR further includes a A1GaAs region. The AlGaAs region includes alternating thin layers of AlAs and GaAs. The alternating thin layers of AlAs and GaAs are arranged such the the AlGaAs region appears as a layer of A1GaAs with appropriate concentrations of Al and Ga.

AlAs/GaAs alloy to enhance n-type doping in AlGaAs distributed bragg reflector

A long wavelength vertical cavity surface emitting laser having a substrate, a first mirror situated on the substrate, an active region situated on the first mirror, a second mirror situated on the active region. The first mirror may have several pairs of layers with an oxidized layer in one or more pairs of that mirror. The substrate may include InP and the mirror components may be compatible with the InP. The one or more layers in the first mirror may be oxidized via a trench-like approach or other arrangement.

InP based long wavelength VCSEL

GaAsSblayers are grown by MOCVD. For lattice matching with InP, x is set to 0.5, while beneficial alternatives include setting x to 0.23, 0.3, and 0.4. During MOVCD, TMGa (or TEGa), TMSb, and AsH(or TBAs) are used to fabricate the GaAsSblayer. Beneficially, the GaAsSbx layer's composition is controlled by the ratio of As to Sb. The MOCVD growth temperature is between 500&#xb0; C. and 650&#xb0; C. The GaAsSblayer is beneficially doped using CClor CBr. A heavily doped GaAsSblayer can be used to form a tunnel junction with n-doped layers of InP, AlInAs, or with lower bandgap materials such as AlInGaAs or InGaAsP. Such tunnel junctions are useful for producing long wavelength VCSELs.

Carbon doped GaAsSb suitable for use in tunnel junctions of long-wavelength VCSELs

A vertical cavity surface emitting laser (VCSEL) structure includes a bottom distributed Bragg reflector (DBR) arranged over a substrate; a metal layer interposed between the bottom DBR and the substrate, wherein the metal layer and bottom DBR form a composite mirror structure. A patterned dielectric layer may be interposed between the metal layer and the bottom DBR to reduce a deleterious chemical reaction between the metal layer and the bottom DBR. The metal layer directly contacts a portion of the bottom DBR to enhance the electrical and thermal conductivity of the VCSEL structure.

Carrier bonded 1550 nm VCSEL with InP substrate removal

A vertical cavity surface emitting laser having an oxidizable layer oxidized with enhanced lateral oxidation. The oxidation may involve adding oxygen in the form of a fluid, with or without other fluid such as water vapor, in the oxidizing environment, and/or in the layer to be oxidized. This oxidation approach may be used for layers with relatively low aluminum content such as in InP based structures, or with high aluminum content such as in GaAs based structures.

Enhanced lateral oxidation

Distributed Bragg reflectors (DBRs), and VCSELs that use such DBRs, comprised of AlP layers on InP substrates. When grown on an InP substrate, if the critical layer thickness (t) of AlP is greater than &#x3bb;/4n, where nis the index of refraction of InP and &#x3bb; is the wavelength, then the DBR can be grown using alternating layers of InP and AlP, wherein the thickness of the AlP is less than the critical thickness. If the critical layer thickness (t) of AlP is greater than &#x3bb;/4n, then the DBR mirror is grown using alternating layers of InP and of an AlP/InP superlattice, wherein the AlP/InP superlattice is comprised of InP and of AlP wherein the thickness of the AlP is less than the critical thickness.

Material system for Bragg reflectors in long wavelength VCSELs

A vertical cavity surface emitting laser having an InP substrate and a lower mirror stack comprised of a plurality of alternating layers of AlPSb and GaPSb over the InP substrate. An InP spacer is over the lower mirror stack. An active region is over the InP spacer, and a tunnel junction is over the active region. Then a top mirror structure comprised of a low-temperature formed first GaAs buffer layer, a high-temperature formed second GaAs seed layer, an insulating structure having an opening, and a GaAs/Al(Ga)As mirror stack that is grown by lateral epitaxial overgrowth.

Long wavelength VCSEL bottom mirror

A vertical cavity surface emitting laser having a GaAs/Al(Ga)As DBR mirror over an InP layer A first GaAs layer is MOCVD grown on an InP layer at a growth temperature of between 400 and 450&deg; C. Then a second GaAs layer is grown by MOCVD at a growth temperature of about 600&deg; C. over the first GaAs layer. A GaAs/Al(Ga)As DBR mirror is then grown over the second GaAs layer. Beneficially, an insulating layer is disposed between the second GaAs layer and the GaAs/Al(Ga)As DBR mirror. The insulating layer includes an opening that exposes the second GaAs layer. Then the GaAs/Al(Ga)As DBR mirror is grown by lateral epitaxial overgrowth. The lower DBR can be comprised of a material that provides an acceptable lattice match with InP layers. A tunnel junction can be formed over an InP active region.

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Plymouth, MN, United States of America

Hoki Kwon