Patent classifications
H01S5/18311
Semiconductor device, semiconductor device package and auto focusing device
A semiconductor device comprises a substrate and a plurality of emitters disposed on the substrate. The emitter may comprise: a first conductive reflection layer having a first reflectivity; an active layer disposed on the first conductive reflection layer; an aperture layer disposed on the active layer and comprising an aperture region and a blocking region surrounding the aperture region; and a second conductive reflection layer disposed on the aperture layer and having a second reflectivity smaller than the first reflectivity. A diameter-to-pitch ratio of the aperture region of the aperture layer is 1:3 to 1:5, wherein the pitch may be defined as the distance between centers of aperture regions of aperture layers of adjacent emitters.
Eye-safe long-range solid-state LIDAR system
A solid-state LIDAR system includes a plurality of lasers, each generating an optical beam having a FOV when energized. A plurality of detectors is positioned in an optical path of the optical beams generated by the plurality of lasers. A FOV of at least one of the plurality of optical beams generated by the plurality of lasers overlaps a FOV of at least two of the plurality of detectors. A controller is configured to generate bias signals at a plurality of laser control outputs that energize a selected group of the plurality of lasers in a predetermined time sequence and is configured to detect a predetermined sequence of detector signals generated by the plurality of detectors.
DENSELY PACKED VCSEL ARRAY
A semiconductor device comprising an array of vertical cavity surface emitting lasers (VCSELs). The semiconductor device includes a first VCSEL having a first active area, a second VCSEL having a second active area, and a bridge connecting the first VCSEL and the second VCSEL. The first active area of the first VCSEL and the second active area of the second VCSEL are arranged along a first crystal axis. The semiconductor device further includes a blocking structure arranged between the first VCSEL and the second VCSEL. the blocking structure is configured to block a propagation of a defect between the first VCSEL and the second VCSEL along the first crystal axis.
FABRICATING SEMICONDUCTOR DEVICES, SUCH AS VCSELS, WITH AN OXIDE CONFINEMENT LAYER
Methods for forming an at least partially oxidized confinement layer of a semiconductor device and corresponding semiconductor devices are provided. The method comprises forming two or more layers of a semiconductor device on a substrate. The layers include an exposed layer and a to-be-oxidized layer. The to-be-oxidized layer is disposed between the substrate and the exposed layer. The method further comprises etching, using a masking process, a pattern of holes that extend through the exposed layer at least to a first surface of the to-be-oxidized layer. Each hole of the pattern of holes extends in a direction that is transverse to a level plane that is parallel to the first surface of the to-be-oxidized layer. The method further comprises oxidizing the to-be-oxidized layer through the pattern of holes by exposing the two or more layers of the semiconductor device to an oxidizing gas to form a confinement layer.
Tailoring of high power VCSEL arrays
Modification of the topology of selected regions of individual VCSEL devices during fabrication is utilized to provide an array output beam with specific characteristics (e.g., “uniform” output power across the array). These physical features include the width of the metal aperture, the width of the modal filter, and/or the geometry of the contact ring structure on the top of the VCSEL device. The modifications may also function to adjust the numerical apertures (NAs) of the devices, the beam waist, wallplug efficiency, and the like.
LIGHT-EMITTING ELEMENT AND METHOD OF MANUFACTURING THE SAME
A light-emitting element includes: a laminated structure body 20 which is formed from a GaN-based compound semiconductor and in which a first compound semiconductor layer 21 including a first surface 21a and a second surface 21b that is opposed to the first surface 21a, an active layer 23 that faces the second surface 21b of the first compound semiconductor layer 21, and a second compound semiconductor layer 22 including a first surface 22a that faces the active layer 23 and a second surface 22b that is opposed to the first surface 22a are laminated; a first light reflection layer 41 that is provided on the first surface 21a side of the first compound semiconductor layer 21; and a second light reflection layer 42 that is provided on the second surface 22b side of the second compound semiconductor layer 22. The first light reflection layer 41 includes a concave mirror portion 43, and the second light reflection layer 42 has a flat shape.
LIGHT SOURCE DEVICE AND DISTANCE MEASURING DEVICE
The disclosed light source device includes a light emitting element including a first reflector, a second reflector, and a resonator spacer portion provided between the first reflector and the second reflector and including an active layer, and emits a first light as a laser beam and a second light as a spontaneous emission light, a light receiving element that determines an amount of the second light, and a determination unit that determines a timing at which the first light oscillates based on a decrease in the amount of the second light determined by the light receiving element.
HIGH SPEED NARROW SPECTRUM MINIARRAY OF VCSELS AND DATA TRANSMISSION DEVICE BASED THEREUPON
An on-chip miniarray of optically-coupled oxide-confined apertures of vertical cavity surface emitting lasers (VCSELs) is realized by etching holes from the chip surface down to at least one aperture layer. Oxidation of the aperture layer results in electrically-isolated apertures suitable for current injection. The lateral distance between the aperture centers and the shape of the aperture is chosen to result in effective interaction of the neighboring optical modes in the related aperture regions through optical field coupling effect causing the interaction-induced splitting of the wavelengths of the optical modes. At least one aperture has a different surface area due to different spacing of the etched holes. Different aperture sizes result in different wavelengths of the coupled modes. Splitting of the cavity modes in a frequency domain 3-100 GHz extends the modulation bandwidth of the device due to photon-photon interaction effects.
Selective deposition of highly reflective coating and/or anti-reflecting coating over apertures of different VCSELs foiining a miniarray allows stabilizing lasing in a single coherent mode of the array. Most preferably, highly reflective coating covers the largest aperture and stabilizes the fundamental mode of the coherent array. Anti-reflecting coatings can be deposited on at least one other aperture to reduce the photon lifetime and increase the homogeneous broadening of the related resonant wavelength. Consequently broadening of the photon-photon interaction resonances between the cavity modes can be controlled. Such resonance broadening allows control over the shape of the current modulation curve of the miniarray of VCSELs with the frequency maximum defined by the splitting of the cavity modes and the broadening defined by the broadening of the photon resonances. An increase in −3dB modulation bandwidth of the VCSEL miniarray up to at least 70 GHz is possible.
Such miniarray of VCSELs enables efficient coupling of the emitted light to a multimode optical fiber with the efficiency of at least 70%.
Vertical-cavity surface-emitting laser with dense epi-side contacts
An emitter may include a substrate, a conductive layer on at least a bottom surface of a trench, and a first metal layer to provide a first electrical contact of the emitter on an epitaxial side of the substrate. The first metal layer may be within the trench such that the first metal layer contacts the conductive layer within the trench. The emitter may further include a second metal layer to provide a second electrical contact of the emitter on the epitaxial side of the substrate, and an isolation implant to block lateral current flow between the first electrical contact and the second electrical contact.
OPTIMIZING A LAYOUT OF AN EMITTER ARRAY
A closely spaced emitter array may include a first emitter comprising a first plurality of structures and a second emitter, adjacent to the first emitter, comprising a second plurality of structures. The first emitter and the second emitter may be configured in the closely spaced emitter array such that different types of structures between the first plurality of structures and the second plurality of structures do not overlap while maintaining close spacing between the first emitter and the second emitter.