摘要:
Quantum wells and associated barriers layers can be grown to include nitrogen (N), aluminum (Al), antimony (Sb), phosphorous (P) and/or indium (In) placed within or about a typical GaAs substrate to achieve long wavelength VCSEL performance, e.g., within the 1260 to 1650 nm range. In accordance with features of the present invention, a vertical cavity surface emitting laser (VCSEL), can include at least one quantum well comprised of InGaAsSb; barrier layers sandwiching said at least one quantum well; and confinement layers sandwiching said barrier layers. A vertical cavity surface emitting laser (VCSEL), can also include at least one quantum well comprised of InGaAsSbN. Barrier layers can be comprised of GaAsN, GaAsP, or AlGaAs. Confinement layers can be comprised of AlGaAs. Quantum wells can include N. Quantum wells can be developed up to and including 50 Å in thickness. Quantum wells can also be developed with a depth of at least 40 meV.
摘要:
VCSELs having upper mirror structures comprised of a semiconductive top DBR, metal contacts, and a top mirror. The top DBR is thick enough for adequate current spreading, but thin enough, being no more than 3.5 microns, to enable easy fabrication of an isolation region. The top mirror, which is over the top DBR, enhances reflectivity. That top mirror is beneficially comprised of a dielectric material, such as TiO2; TiO2+SiO2 (robust and reliable); TiO2+Al2O3 (good thermal conductivity); or Si+MgO, or of a metal. The top mirror is beneficially formed using a vacuum deposition method, such as e-beam or sputtering. The metal contacts are formed on the top DBR. The VCSELs further include a substrate with an electrical contact, a bottom DBR, a bottom spacer, an active region, and a top spacer. Such VCSELs are particularly beneficial at long wavelengths.
摘要:
An active region of a VCSEL at one (i.e., n doped) end having an expanded effectively undoped region, and another (i.e., p doped) end having a significantly doped region up to or even including a portion of the active region. A previous way had heavy doping of the n and p doped regions up to the active region, at least close to it or even partially into it.
摘要:
A laser structure is provided with two current confining layers of a material that is subject to oxidation in the presence of an oxidizing agent. The laser structure is shaped to expose edges of the current confining layers to permit the edges to be exposed to the oxidizing agent. The current confining layers are oxidized selectively to create electrically resistive material at the oxidized portions and electrically conductive material at the unoxidized portions. The unoxidized portions of the layers are surrounded by the oxidized and electrically resistive portions in order to direct current from one electrical contact pad by passing through a preselected portion of an active region of the laser. The laser structure can be a vertical cavity surface emitting laser. The device achieves the current confining and directing function without the need to use ion bombardment or implantation to provide the current confining structure within the body of the laser.
摘要:
A method for preparing a VCSEL can use MBE for: growing a first conduction region over a first mirror region; growing an active region over the first conduction region opposite of the first mirror region, including: (a) growing a quantum well barrier having In1-xGaxP(As); (b) growing an transitional layer having one or more of GaP, GaAsP, or GaAs; (c) growing a quantum well layer having In1-zGazAsyP1-y; (d) growing another transitional layer have one or more of GaP, GaAsP, or GaAs; (e) repeating processes (a) through (d) over a plurality of cycles; and (f) growing a quantum well barrier having In1-xGaxP(As); growing a second conduction region over the active region opposite of the first conduction region, wherein: x ranges from 0.77 to 0.50; y ranges from 0.7 to 1; and z ranges from 0.7 to 0.99.
摘要:
A semiconductor structure configured for use in a VCSEL or RCLED. The semiconductor structure includes an oxidizing layer constructed from materials that can be oxidized during a lithographic process so as to create an oxide aperture. The semiconductor structure further includes a number of layers near the oxidizing layer. A passivation material is disposed on the layers near the oxidizing layer. The passivation material is configured to inhibit oxidation of the layers.
摘要:
Methods for manufacturing a polarization pinned vertical cavity surface emitting laser (VCSEL). Steps include growing a lower mirror on a substrate; growing an active region on the lower mirror; growing an upper mirror on the active region; depositing a grating layer on the upper mirror; and etching a grating into the grating layer.
摘要:
A VCSEL with nearly planar intracavity contact. A bottom DBR mirror is formed on a substrate. A first conduction layer region is formed on the bottom DBR mirror. An active layer, including quantum wells, is on the first conduction layer region. A trench is formed into the active layer region. The trench is formed in a wagon wheel configuration with spokes providing mechanical support for the active layer region. The trench is etched approximately to the first conduction layer region. Proton implants are provided in the wagon wheel and configured to render the spokes of the wagon wheel insulating. A nearly planar electrical contact is formed as an intracavity contact for connecting the bottom of the active region to a power supply. The nearly planar electrical contact is formed in and about the trench.
摘要:
An optical device for improving conduction and reflectivity and minimizing absorption. The optical device includes a first mirror comprising a first plurality of mirror periods designed to reflect an optical field at a predetermined wavelength, where the optical field has peaks and nulls. Each of the plurality of mirror periods includes a first layer of having a high carrier mobility, a second layer having lower carrier mobility, and a first compositional ramp between the first and second layers. The thicknesses of the first and second layers for at least a portion of the first plurality of mirror periods are established such that the nulls of the optical field occur within the first layer and not within the compositional ramp. At least the portion of the first layers within the first plurality of mirror periods include elevated doping concentrations at locations of the nulls of the optical field.
摘要:
A polarization pinned vertical cavity surface emitting laser (VCSEL). A VCSEL designed to be polarization pinned includes an upper mirror. An active region is connected on the upper mirror. A lower mirror is connected to the active region. A grating layer is deposited to the upper mirror. The grating layer includes a low index of refraction layer formed by deposition on the upper mirror. The grating layer further includes a high index of refraction layer formed by deposition on the low index of refraction layer. A grating is formed into the grating layer.