A VCSEL includes an active region between a top distributed Bragg reflector (DBR) and a bottom DBR each having alternating GaAs and AlGaAs layers. The active region includes quantum wells (QW) confined between top and bottom GaAs-containing current-spreading layers (CSL), an aperture layer having an optical aperture and a tunnel junction layer above the QW. A GaAs intermediate layer configured to have an open top air gap is disposed over a boundary layer of the active region and the top DBR. The air gap is made wider than the optical aperture and has a height equal to one quarter of VCSEL's emission wavelength in air. The top DBR is attached to the intermediate layer by applying wafer bonding techniques. VCSEL output, the air gap, and the optical aperture are aligned on the same optical axis. The bottom DBR is epitaxially grown on a silicon or a GaAs substrate.

A VCSEL may include an n-type substrate layer and an n-type bottom mirror on a surface of the n-type substrate layer. The VCSEL may include an active region on the n-type bottom mirror and a p-type layer on the active region. The VCSEL may include an oxidation layer over the active region to provide optical and electrical confinement of the VCSEL. The VCSEL may include a tunnel junction over the p-type layer to reverse a carrier type of an n-type top mirror. Either the oxidation layer is on or in the p-type layer and the tunnel junction is on the oxidation layer, or the tunnel junction is on the p-type layer and the oxidation layer is on the tunnel junction. The VCSEL may include the n-type top mirror over the tunnel junction, a top contact layer over the n-type top mirror, and a top metal on the top contact layer.

An acoustic sensor is disclosed, the sensor including a laser and a membrane configured to vibrate in the presence of an acoustic wave, and to reflect radiation emitted by the laser back toward the laser to produce a self-mixing interference effect corresponding to the acoustic wave. The sensor also includes a cavity separating the membrane from the laser and extending rearward of a radiation-emitting surface of the laser, a majority volume of the cavity being disposed rearward of the radiation-emitting surface of the laser. Also disclosed is an apparatus including the acoustic sensor, and a method of manufacturing the acoustic sensor.

Methods and structures for forming vertical-cavity light-emitting devices are described. An n-side or bottom-side layer may be laterally etched to form a porous semiconductor region and converted to a porous oxide. The porous oxide can provide a current-blocking and guiding layer that aids in directing bias current through an active area of the light-emitting device. Distributed Bragg reflectors may be fabricated on both sides of the active region to form a vertical-cavity surface-emitting laser. The light-emitting devices may be formed from III-nitride materials.

A VCSEL includes an active region between a top distributed Bragg reflector (DBR) and a bottom DBR each having alternating GaAs and AlGaAs layers. The active region includes quantum wells (QW) confined between top and bottom GaAs-containing current-spreading layers (CSL), an aperture layer having an optical aperture and a tunnel junction layer above the QW. A GaAs intermediate layer configured to have an open top air gap is disposed over a boundary layer of the active region and the top DBR. The air gap is made wider than the optical aperture and has a height equal to one quarter of VCSEL's emission wavelength in air. The top DBR is attached to the intermediate layer by applying wafer bonding techniques. VCSEL output, the air gap, and the optical aperture are aligned on the same optical axis. The bottom DBR is epitaxially grown on a silicon or a GaAs substrate.

An electrically injected vertical-cavity surface emitting laser (VCSEL) and a method of manufacturing the same is disclosed. The electrically injected VCSEL includes a non-c-plane substrate and a nanoporous bottom distributed Bragg reflector (DBR) comprising a plurality of alternating highly doped III-nitride layers and unintentionally doped III-nitride layers formed above the substrate.

A semiconductor device fabrication method in which a growing process is followed by a capping process in which a phosphor containing material cap layer is deposited over a final GaAs based layer. The wafer, containing many such substrates, can be removed from the reaction chamber to continue processing at a later time without creating an oxide layer on the final GaAs based layer. In continuing processing, a decomposition process selectively decomposes the phosphor containing material cap layer, after which a regrowing process is performed to grow additional layers of the device structure. The capping, decomposition and regrowth processes can be repeated multiple times on the semiconductor devices on the wafer during device fabrication.

Disclosed herein is a system comprising: an optical system with a focal plane; an apparatus at the focal plane; a filter; wherein the apparatus comprises an array of vertical-cavity surface-emitting lasers (VCSELs) on a first substrate and an array of detectors on a second substrate, the detectors configured to detect laser beams that are emitted by the VCSELs and backscattered by an object; wherein the first substrate is mounted to the second substrate and is configured to allow the laser beams that are emitted by the VCSELs and backscattered by the object to transmit through the first substrate and reach the detectors; wherein the filter is configured to prevent light other than the laser beams from passing.

A high-contrast grating (HCG) structure and method of fabrication. The grating of the HCG is formed over a structural spacer layer, allowing a wider range of grating patterns, such as post and other forms which are lack structural support when fabricated over an air spacing beneath the grating elements. The technique involves etching the HCG grating, followed by oxidizing through this HCG grating into an oxide spacer layer beneath it creating a low-index area beneath the grating. This form of HCG reflector can be utilizes as upper and/or lower reflectors in fabricating vertical cavity surface emitting lasers (VCSELs).

A widely tunable vertical-cavity surface-emitting laser (VCSEL) having a semiconductor cavity followed by an air-gap over which is a movable reflector. Lasing wavelength is controlled by a combination of the resonance of the semiconductor cavity, which is fixed, and the resonance of the air cavity, which can be changed by moving the reflector. Tuning range and slope of the VCSEL are increased by configuring the semiconductor cavity to be antiresonant at the center of the tuning range, which forces electromagnetic energy to be confined more strongly in the air gap than in the semiconductor, thus making emission wavelength more sensitive to the displacement of the tuning mirror.