Abstract:
Novel ICL layering designs, ridge waveguide architectures, and processing protocols that will significantly lower the optical losses and improve the power conversion efficiencies of interband cascade lasers designed for both DFB single-mode and high-power applications. The semiconductor top cladding and metal contact layers are eliminated or significantly reduced. By instead using a dielectric or air top clad, or dielectric or air layers to supplement a thin top clad, in conjunction with lateral current injection and weak index- guiding,, the present invention will substantially reduce the internal loss of such ICLs, resulting in lower lasing threshold, higher efficiency, and higher maximum power.
Abstract:
A tunable surface emitting laser includes on a semiconductor substrate (1) a first reflecting mirror (2); an active layer (4) on the first reflecting mirror which may be a DBR; a current confinement layer (6) resulting from partial oxidation of an AlGaAs layer; a conductive layer (7) on the current confinement layer (6) for providing a bias current to the active region; support portions (8) made from electrically insulating material like undoped GaAs; and a conductive film (9) which is provided above the conductive layer via a support portion (8) and which comprises a second reflecting mirror (11) like a HCG. A gap portion (14) is formed between the conductive layer (7) and the conductive film (9). The conductive layer (7) includes a high resistivity region (13) provided between the support portion (8) and the central current guiding region of the current confinement layer (6). Breakdown voltage of the tuning part is increased and rapid wavelength tuning via corresponding currents provided to the electrodes (12) is enabled allowing for faster movement of the second reflector (11).
Abstract:
A surface emitting laser apparatus is formed using a patterned silicon-on- insulator (SOI)-like substrate which is patterned with a buried sub-wavelength high contrast grating and adapted for bonding of a half-VCSEL device containing at least an active region and an upper mirror, to create a VCSEL. The wavelength of the VCSEL, or any individual VCSEL within an array of VCSEL devices, can be set in response to changing HCG characteristics of the lower mirror in the SOI-like substrate, or in the region above the lower mirror within the half-VCSEL. The inventive VCSEL device and fabrication method are beneficial for a number of application and devices.
Abstract:
Light emitting devices and methods of fabricating light emitting devices having a current blocking mechanism below the wire bond pad (22) are provided. The current blocking mechanism may be a reduced conduction region (30) in an active region (14) of the device. The current blocking mechanism could be a damage region of a layer on which a contact (18) is formed. The current blocking mechanism could be a Schottky contact between an ohmic contact (18) and the active region (14) of the device. A semiconductor junction, such as a PN junction could also be provided between the ohmic contact (18) and the active region (14).
Abstract:
La présente invention concerne un laser semi-conducteur de puissance à faibles divergence et astigmatisme, et ce laser est caractérisé en qu'il comporte, dans une couche active (4), une première partie (7) sous forme de ruban étroit monomode à guidage transverse par l'indice, terminée par une deuxième partie (8) s'évasant depuis la première partie, également à guidage transversé par l'indice.
Abstract:
A vertical cavity having a tunnel junction surface emitting laser (VCSEL) for emitting long wavelength light (i.e., 1200 to 1800 nanometers, though it is contemplated that the structures and techniques are applicable to other wavelength VCSELs). The tunnel junction may be isolated with an implant down into the top mirror through the tunnel junction and p-layer and a trench around the VCSEL down to at least past the tunnel junction. The trench may result in reduced capacitance and D.C. isolation of the tunnel junction. The implant is performed after the trench is made. Some of the implant may enter the bottom of the trench into the bottom mirror for some further isolation for the tunnel junction of the VCSEL. Further isolation and some current confinement may be provided with lateral oxidation of a layer below the tunnel junction. Internal trenches may be made from the top of the VCSEL vertically down to the oxidizable layer below the tunneljunction. Oxidation of that layer via these trenches may provide further isolation of the tunnel junction. Also, a bonding pad connected to a contact on the VCSEL with a bridge may have an open trench about their periphery for their isolation. Internal trenches may be placed on the pad and its bridge that go down vertically to the oxidizable layer. Oxidation via these trenches may provide further isolation for the pad and bridge if the latter is present.
Abstract:
A vertical cavity surface emitting laser [100] with a current guide comprised of an ion (160) implant region and an oxide structure (140). The oxide structure (140) is beneficially formed first, then, a gain guide ion implant region (160) is formed in or below the oxide structure (140). The ion (160) implant region extends into an active region (22). The energy and dosage used when forming the ion (160) implant gain guide can be selected to control the lateral sheet resistance and the active region's (22) non-radiative recombination centers.
Abstract:
The invention concerns a stripe laser diode element exhibiting longitudinal direction of propagation in the main direction of propagation of a laser light and having contacts in longitudinal direction of propagation on one surface with the purpose of impressing a current on the element. The surface in defined by edges crosswise to the longitudinal direction. An absorption region is formed in the area of said edges.
Abstract:
A surface emitting laser with spatially varying optical loss to provide single mode operation. The optical loss may be introduced with an anti-phased ohmic contacts (4, 5). Current injection may be constricted to a diameter that is different than the diameter of the ohmic aperture (32), allowing for optimization of carrier profiles for high-speed performance. Methods for index guiding are introduced to further the reproducibility of the invention.
Abstract:
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.