A corrected mesa structure for a VCSEL device is particularly configured to compensate for variations in the shape of the created oxide aperture that result from anisotropic oxidation. In particular, a corrected mesa shape is derived by determining the shape of an as-created aperture formed by oxidizing a circular mesa structure, and then ascertaining the compensation required to convert the as-created shape into a desired (“target”) shaped aperture opening. The compensation value is then used to modify the shape of the mesa itself such that a following anisotropic oxidation yields a target-shaped oxide aperture.

A light source package structure is provided. The light source package structure includes a substrate, an upper electrode layer, a surrounding wall, a light emitting unit, an adhesive, and a light permeable element. The surrounding wall is annular with step structure and includes an upper tread surface arranged away from the substrate, an upper riser surface connected to an inner edge of the upper tread surface, a lower tread surface disposed at an inner side of the upper riser surface, an accommodating groove disposed between the lower tread surface and the upper riser surface, and a lower riser surface connected to an inner edge of the lower tread surface and arranged away from the upper tread surface. The lower riser surface and the first surface jointly define a receiving space.

Trenched VCSEL emitter structures are described. In an embodiment, an emitter structure includes a cluster of non-uniformly distributed emitters in which each emitter includes an inside mesa trench and an oxidized portion of an oxide aperture layer extending from the inside mesa trench. An outside moat trench is located adjacent the inside mesa trench and is formed to a depth past the oxide aperture layer.

A VCSEL device having non-coaxial-with-one-another apertures and/or rotationally asymmetric apertures formed in layer(s) of the VCSEL structure to define more than one spatial mode in a light output in operation of the device. An array of such VCSEL devices configured to have different spatial modes at the output of different constituent VCSEL devices. Spatial asymmetry of structure of the constituent VCSEL devices and, therefore, arrays of VCSEL devices causes the overall light output to form an irregular grid of output spots of light. When the VCSEL array is equipped with an appropriate lens array, the spatial components of the light output of the VCSEL array are caused to overlap in the far at the imaging plane in a multiple spatial (and spectral) mode fashion, thereby reducing speckle in imaging applications.

An exemplary embodiment of the invention relates to a method of fabricating a radiation emitter (100) comprising the steps of fabricating a layer stack (10) that comprises a first reflector (12), an active region (13), an oxidizable layer (21-24), and a second reflector (14); and locally removing the layer stack (10), and thereby forming a mesa (M) of the radiation emitter (100), wherein said mesa (M) comprises the first reflector (12), the active region (13), the oxidizable layer (21-24) and the second reflector (14), wherein before or after locally removing the layer stack (10) and forming said mesa (M) the following steps are carried out: vertically etching blind holes (30) inside the layer stack (10), wherein the blind holes (30) vertically extend at least to the oxidizable layer (21-24) and expose the oxidizable layer (21-24); and oxidizing the oxidizable layer (21-24) via the sidewalls (31) of the blind holes (30) in lateral direction, wherein from each hole an oxidation front (32) radially moves outwards and wherein the etching is terminated before the entire oxidizable layer (21-24) is oxidized, thereby forming at least two unoxidized apertures, (40) each of which is limited by at least three oxidation fronts (32), inside the mesa.

A MEMS-based vertical cavity surface emitting laser (VCSEL) includes an embedded photodiode. A representative VCSEL includes a distributed Bragg reflector (DBR), a photodiode structure located within the distributed Bragg reflector, an active region overlying the distributed Bragg reflector, and a MEMS upper reflector disposed over the active region. The VCSEL may be configured as an optical sensor. The laser cavity and hence a working wavelength of the sensor may be tuned by modulating the MEMS reflector such as through an applied voltage.

An optoelectronic device includes: (i) a semiconductor substrate doped with a first level of n-type dopants, (ii) a contact semiconductor layer disposed over the semiconductor substrate and doped with a second level of n-type dopants, larger than the first level, (iii) an upper distributed Bragg-reflector (DBR) stack disposed over the contact semiconductor layer and including alternating first and second epitaxial semiconductor layers having respective first and second indexes of refraction that differ from one another in a predefined wavelength band, (iv) a set of epitaxial layers disposed over the upper DBR, the set of epitaxial layers includes one or more III-V semiconductor materials and defines: (a) a quantum well structure, and (b) a confinement layer, and (v) a lower DBR stack disposed over the set of epitaxial layers, opposite the upper DBR, and including alternating dielectric and semiconductor layers.

A vertical cavity surface emitting laser (VCSEL) device includes an oxide aperture layer positioned in close proximity to the active region of the device, typically within the cavity itself, as opposed to being positioned in the top DBR of the VCSEL. Reducing the spacing between the active region and the oxide aperture layer has been found to reduce the spread of current across the surface of the active region, allowing for a lower threshold current to be achieved. The closer positioning of the oxide aperture layer also reduced optical absorption and series resistance. The oxide aperture layer may be located at the first null in the standing wave pattern between the active region and the top DBR to minimize divergence of the beam and control the optical mode.

An array of surface-emitting lasers is provided. The array outputs high brightness in a unipolar way. The array comprises a stress-adjustment unit and a plurality of epitaxial device units. The stress-adjustment unit is used to adjust stress. The stress from a substrate is used to select a laser mode for an aperture unit. The selection of the laser mode is enhanced for the aperture unit without sacrificing driving current. Low current operation is achieved in a single mode for effectively reducing volume and further minimizing the size of the whole array to achieve high-quality laser output. An object can be scanned by the outputted laser to obtain a clear image with a high resolution. Hence, the present invention is applicable for face recognition with high recognition and high security.

A method of manufacturing a surface emitting laser according to an embodiment of the present disclosure includes the following two steps: (1) a step of forming a semiconductor stacked structure on a substrate, the semiconductor stacked structure including an active layer, a first DBR layer of a first electrical conduction type, and a second DBR layer of a second electrical conduction type, the first DBR layer and the second DBR layer sandwiching the active layer, the second electrical conduction type being different from the first electrical conduction type; and (2) a step of forming a mesa section at a portion on the second DBR layer side in the semiconductor stacked structure and then forming an annular diffusion region of the first electrical conduction type at an outer edge of the mesa section by impurity diffusion from a side surface of the mesa section, the mesa section including the second DBR layer, the mesa section not including the active layer.