摘要:
A gallium nitride device substrate comprises a layer of gallium nitride containing an additional lattice parameter altering element located over a substitute substrate.
摘要:
A gallium nitride device substrate comprises a layer of gallium nitride containing an additional lattice parameter altering element located over a substitute substrate.
摘要:
The present invention provides a ring laser system comprising forming an optical core by an epitaxial layer overgrowth over an intermediate layer, forming multi-quantum wells adjacent to the optical core and forming an outer structure further comprising a total internal reflector, wherein forming photons within the multi-quantum wells further comprises circulating the photons within the ring laser structure comprising the outer structure, the multi-quantum wells, and the optical core.
摘要:
An optical assembly includes an optical subassembly containing a prefabricated long wavelength laser optically coupled to a prefabricated short wavelength laser located in a housing. The optical subassembly may be removably installed in the housing in which the short wavelength laser is contained. The short wavelength laser optically pumps the long wavelength laser resulting in a long wavelength laser output. The optical subassembly allows the independent fabrication, optimization and testing of the short wavelength laser and the long wavelength laser.
摘要:
A method for growing a crystalline layer that includes a first material on a growth surface of a crystalline substrate of a second material, wherein the first material and the second material have different lattice constants. A buried layer is generated in the substrate such that the buried layer isolates a layer of the substrate that includes the growth surface from the remainder of the substrate. The second material is then deposited on the growth surface at a growth temperature. The isolated layer of the substrate has a thickness that is less than the thickness at which defects are caused in the crystalline lattice of the first material by the second material crystallizing thereon. The buried layer is sufficiently malleable at the growth temperature to allow the deformation of the lattice of the isolated layer without deforming the remainder of the substrate. The present invention may be utilized for growing III-V semiconducting material layers on silicon substrates. In the case of silicon-based substrates, the buried layer is preferably SiO2 that is sufficiently malleable at the growth temperature to allow the deformation of the isolated substrate layer.
摘要:
The device is an optoelectronic device or transparent waveguide device that comprises a growth surface, a growth mask, an optical waveguide core mesa and a cladding layer. The growth mask is located on the semiconductor surface and defines an elongate growth window having a periodic grating profile. The optical waveguide core mesa is located in the growth window and has a trapezoidal cross-sectional shape. The cladding layer covers the optical waveguide core mesa and extends over at least part of the growth mask. Such devices are fabricated by providing a wafer comprising a growth surface, growing an optical waveguide core mesa on the growth surface by micro-selective area growth at a first growth temperature and covering the optical waveguide core mesa with cladding material at a second growth temperature, lower than the first growth temperature.
摘要:
The present invention provides a ring laser system comprising forming an optical core by an epitaxial layer overgrowth over an intermediate layer, forming multi-quantum wells adjacent to the optical core and forming an outer structure further comprising a total internal reflector, wherein forming photons within the multi-quantum wells further comprises circulating the photons within the ring laser structure comprising the outer structure, the multi-quantum wells, and the optical core.
摘要:
The device is an optoelectronic device or transparent waveguide device that comprises a growth surface, a growth mask, an optical waveguide core mesa and a cladding layer. The growth mask is located on the semiconductor surface and defines an elongate growth window having a periodic grating profile. The optical waveguide core mesa is located in the growth window and has a trapezoidal cross-sectional shape. The cladding layer covers the optical waveguide core mesa and extends over at least part of the growth mask. Such devices are fabricated by providing a wafer comprising a growth surface, growing an optical waveguide core mesa on the growth surface by micro-selective area growth at a first growth temperature and covering the optical waveguide core mesa with cladding material at a second growth temperature, lower than the first growth temperature.
摘要:
In one aspect, a VCSEL includes a base region that has a vertical growth part laterally adjacent a first optical reflector and a lateral growth part that includes nitride semiconductor material vertically over at least a portion of the first optical reflector. An active region has at least one nitride semiconductor quantum well vertically over at least a portion of the lateral growth part of the base region and includes a first dopant of a first electrical conductivity type. A contact region includes a nitride semiconductor material laterally adjacent the active region and a second dopant of a second electrical conductivity type opposite the first electrical conductivity type. A second optical reflector is vertically over the active region and forms with the first optical reflector a vertical optical cavity overlapping at least a portion of the at least one quantum well of the active region. A method of fabricating a VCSEL also is described.
摘要:
The electroabsorption modulator comprises a p-i-n junction structure that includes an active layer, a p-type cladding layer and an n-type cladding layer with the active layer sandwiched between the cladding layers. The electroabsorption modulator additionally comprises a quantum well structure located within the active layer. The p-type cladding layer comprises a layer of heavily-doped low-diffusivity p-type semiconductor material located adjacent the active layer that reduces the extension of the depletion region into the p-type cladding layer when a reverse bias is applied to the electroabsorption modulator. The reduced extension increases the strength of the electric field applied to the quantum well structure by a given reverse bias voltage. The increased field strength increases the extinction ratio of the electroabsorption modulator.