In some embodiments, the present disclosure relates to a vertical cavity surface emitting laser (VCSEL) device that includes a microlens arranged over a reflector stack. The reflector stack comprises alternating reflector layers of a first material and a second material. The microlens stack includes a first lens layer, a second lens layer arranged over the first lens layer, and a third lens layer arranged over the second lens layer. The first lens layer comprises a first average concentration of a first element and has a first width. The second lens layer comprises a second average concentration of the first element greater than the first average concentration and has a second width smaller than the first width. The third lens layer comprises a third average concentration of the first element greater than the second average concentration and has a third width smaller than the second width.

A surface-emitting laser device according to an embodiment comprises: a first electrode; a substrate arranged on the first electrode; a first reflection layer arranged on the substrate; an active region arranged on the first reflection layer and including a cavity; an opening region arranged on the active region and including an aperture and an insulation region; a second reflection layer arranged on the opening region; a second electrode arranged on the second reflection layer; and a delta doping layer arranged in the opening region. The thickness of the insulation region becomes thinner in the direction of the aperture, and the delta doping layer can be arranged at the aperture.

A vertical cavity light-emitting element comprises a substrate, a first multilayer reflector formed on the substrate, a semiconductor structure layer formed on the first multilayer reflector and including a light emitting layer, a second multilayer reflector formed on the semiconductor structure layer and constituting a resonator together with the first multilayer reflector, and a light guide layer configured to form a light guide structure including a center region extending in a direction perpendicular to the upper surface of said substrate between the first and second multilayer reflectors and including a light emission center of the light-emitting layer and a peripheral region provided around the center region and having a smaller optical distance between the first and second multilayer reflectors than that in the center region. The second multilayer reflector has a flatness property over the center region and the peripheral region.

A semiconductor vertical resonant cavity light source includes an upper and lower mirror that define a vertical resonant cavity. An active region is within the cavity for light generation between the upper and lower mirror. At least one cavity spacer region is between the active region and the upper mirror or lower mirror. The cavity includes an inner mode confinement region and an outer current blocking region. An index guide in the inner mode confinement region is between the cavity spacer region and the upper or lower mirror. The index guide and outer current blocking region each include a lower and upper epitaxial material layer thereon with an epitaxial interface region in between. At least a top surface of the lower material layer includes aluminum in the interface region throughout a full area of an active part of the vertical light source.

The present invention relates to a vertical cavity surface emitting laser (VCSEL) and a manufacturing method thereof, and more specifically, to a high-efficiency oxide VCSEL which emits laser beams having a peak wavelength of 860 nm, and a manufacturing method thereof.

A vertical cavity surface emitting laser includes: a supporting base; and a post including an upper distributed Bragg reflecting region, an active layer, and a lower distributed Bragg reflecting region. The upper distributed Bragg reflecting region, the active layer, and the lower distributed Bragg reflecting region are arranged on the supporting base. The lower distributed Bragg reflecting region includes first semiconductor layers and second semiconductor layers alternately with each of the first semiconductor layers having a refractive index lower than that of each of the second semiconductor layers. The upper distributed Bragg reflecting region includes first layers and second layers alternately with each of the first layers having a group III-V compound semiconductor portion and a group III oxide portion. The group III-V compound semiconductor portion contains aluminum as a group III constituent element, and the group III oxide portion surrounds the group III-V compound semiconductor portion.

A light emitting element of the present disclosure includes a compound semiconductor substrate 11, a stacked structure 20 including a GaN-based compound semiconductor, a first light reflection layer 41, and a second light reflection layer 42. The stacked structure 20 includes, in a stacked state a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22. The first light reflection layer 41 is disposed on the compound semiconductor substrate 11 and has a concave mirror section 43. The second light reflection layer 42 is disposed on a second surface side of the second compound semiconductor layer 22 and has a flat shape. The compound semiconductor substrate 11 includes a low impurity concentration compound semiconductor substrate or a semi-insulating compound semiconductor substrate.

An in-plane-emitting semiconductor diode laser employs a surface-trapped optical mode existing at a boundary between a distributed Bragg reflector and a homogeneous medium, dielectric or air. The device can operate in both TM-polarized and TE-polarized modes. The mode exhibits an oscillatory decay in the DBR away from the surface and an evanescent decay in the dielectric or in the air. The active region is preferably placed in the top part of the DBR close to the surface. The mode behavior strongly depends on the wavelength of light, upon increase of the wavelength the mode becomes more and more extended into the homogeneous medium, the optical confinement factor of the mode in the active region drops until the surface-trapped mode vanishes. Upon a decrease of the wavelength, the leakage loss of the mode into the substrate increases. Thus, there is an optimum wavelength, at which the laser threshold current density is minimum, and at which the lasing starts. This optimum wavelength is temperature-stabilized, and shifts upon temperature increase at a low rate less than 0.1 nm/K, indicating wavelength-stabilized operation of the device. The approach applies also to semiconductor optical amplifiers or semiconductor gain chips which are also wavelength-stabilized. Reflectivity of the surface-trapped mode from an uncoated facet of the device can be extremely low, also <1E-4 or even <1E-5 which is particularly advantageous for amplifiers or gain chips. For diode lasers, a specific intermediate reflective coating can be deposited on the facet to put its reflectivity into a range from 0.5% to 3%, which lies within targeted values for lasers. An optical integrated circuit can employ wavelength-stabilized amplifiers operating in a surface-trapped mode, wherein such devices amplify light propagating along a dielectric waveguide.

An optoelectronic device includes a semiconductor substrate. A first set of thin-film layers is disposed on the substrate and defines a lower distributed Bragg-reflector (DBR) stack. A second set of thin-film layers is disposed over the lower DBR stack and defines an optical emission region, which is contained in a mesa defined by multiple trenches, which are disposed around the optical emission region without fully surrounding the optical emission region. A third set of thin-film layers is disposed over the optical emission region and defines an upper DBR stack. Electrodes are disposed around the mesa in gaps between the trenches and are configured to apply an excitation current to the optical emission region.

An in-plane-emitting semiconductor diode laser employs a surface-trapped optical mode existing at a boundary between a distributed Bragg reflector and a homogeneous medium, dielectric or air. The device can operate in both TM-polarized and TE-polarized modes. The mode exhibits an oscillatory decay in the DBR away from the surface and an evanescent decay in the dielectric or in the air. The active region is preferably placed in the top part of the DBR close to the surface. The mode behavior strongly depends on the wavelength of light, upon increase of the wavelength the mode becomes more and more extended into the homogeneous medium, the optical confinement factor of the mode in the active region drops until the surface-trapped mode vanishes. Upon a decrease of the wavelength, the leakage loss of the mode into the substrate increases. Thus, there is an optimum wavelength, at which the laser threshold current density is minimum, and at which the lasing starts. This optimum wavelength is temperature-stabilized, and shifts upon temperature increase at a low rate less than 0.1 nm/K, indicating wavelength-stabilized operation of the device. The approach applies also to semiconductor optical amplifiers or semiconductor gain chips which are also wavelength-stabilized. Reflectivity of the surface-trapped mode from an uncoated facet of the device can be extremely low, also <1E4 or even <1E5 which is particularly advantageous for amplifiers or gain chips. For diode lasers, a specific intermediate reflective coating can be deposited on the facet to put its reflectivity into a range from 0.5% to 3%, which lies within targeted values for lasers. An optical integrated circuit can employ wavelength-stabilized amplifiers operating in a surface-trapped mode, wherein such devices amplify light propagating along a dielectric waveguide.