Abstract: A monolithic edge-emitting semiconductor diode array chip (100) comprises a one-dimensional array (70) of diode emitters (50), such as laser diodes, superluminescent diodes or semiconductor optical amplifiers. Semiconductor layers are arranged on a conductive substrate (1) and include active region layers (14) arranged between upper and lower cladding layers (12, 16) and separation layers (4, 5) arranged between the conductive substrate (1) and the lower cladding layer (16). The diode emitters (50) are formed by respective ridges (9) that are separated by trenches (25) which are sufficiently deep to penetrate into the separation layers (4, 5). Each diode (50) has its own upper and lower contacts (22, 24) that allow each diode (50) to be independently drivable with a current source driver circuit connected to push a modulated push current through its associated diode and/or a current sink connected to extract a modulated pull current through its associated diode.

Abstract: An edge-emitting semiconductor laser diode chip 15 with mutually opposed front and back end facet mirrors 22, 24. First and second ridges 261, 262 extend between the chip end facets 22, 24 to define first and second waveguides in an active region layer. Low and high slope efficiency laser diodes are thus formed that are independently drivable by respective electrode pairs 211, 231 and 212, 232. The single chip 15 thus incorporates two laser diodes sharing a common heterostructure, one with low slope efficiency optimized for low power operation with good power stability against temperature variations and random threshold current fluctuations in the close-to-threshold power regime, and the other with high slope efficiency optimized for high wall plug efficiency operation at higher output powers when the chip is operating far above threshold.

Abstract: An edge-emitting semiconductor laser diode chip 15 with mutually opposed front and back end facet mirrors 22, 24. First and second ridges 261, 262 extend between the chip end facets 22, 24 to define first and second waveguides in an active region layer. Low and high slope efficiency laser diodes are thus formed that are independently drivable by respective electrode pairs 211, 231 and 212, 232. The single chip 15 thus incorporates two laser diodes sharing a common heterostructure, one with low slope efficiency optimized for low power operation with good power stability against temperature variations and random threshold current fluctuations in the close-to-threshold power regime, and the other with high slope efficiency optimized for high wall plug efficiency operation at higher output powers when the chip is operating far above threshold.

Abstract: Superluminescent light emitting diode, SLED, devices and modules are provided. A multi-wavelength SLED device is fabricated by sequentially depositing adjacent epitaxial stacks onto a substrate to form a monolithic chip structure. Each epitaxial stack includes n-type layers, active layers and p-type layers. A ridge is formed in the p-type layers between the end facets of the chip to induce a waveguiding region in the active layers. Different ones of the epitaxial stacks emit at different wavelength ranges. A module is made by packaging one of the above SLED devices with another SLED device, with one inverted relative to the other to form a triangle of emitters as viewed end on, for example a triangle of red, green and blue emitters. The SLED devices and modules may find use in projection, endoscopic, fundus imaging and optical coherence tomography systems.

Abstract: Superluminescent light emitting diode, SLED, devices and modules are provided. A multi-wavelength SLED device is fabricated by sequentially depositing adjacent epitaxial stacks onto a substrate to form a monolithic chip structure. Each epitaxial stack includes n-type layers, active layers and p-type layers. A ridge is formed in the p-type layers between the end facets of the chip to induce a waveguiding region in the active layers. Different ones of the epitaxial stacks emit at different wavelength ranges. A module is made by packaging one of the above SLED devices with another SLED device, with one inverted relative to the other to form a triangle of emitters as viewed end on, for example a triangle of red, green and blue emitters. The SLED devices and modules may find use in projection, endoscopic, fundus imaging and optical coherence tomography systems.

Abstract: A group III-nitride semiconductor device comprises a light emitting semiconductor structure comprising a p-type layer and an n-type layer operable as a light emitting diode or laser. On top of the p-type layer there is arranged an n+ or n++-type layer of a group III-nitride, which is transparent to the light emitted from the underlying semiconductor structure and of sufficiently high electrical conductivity to provide lateral spreading of injection current for the light-emitting semiconductor structure.

Abstract: A group III-nitride semiconductor device comprises a light emitting semiconductor structure comprising a p-type layer and an n-type layer operable as a light emitting diode or laser. On top of the p-type layer there is arranged an n+ or n++-type layer of a group III-nitride, which is transparent to the light emitted from the underlying semiconductor structure and of sufficiently high electrical conductivity to provide lateral spreading of injection current for the light-emitting semiconductor structure.

Abstract: A low power, side-emitting semiconductor laser diode is provided. The laser diode is formed from a semiconductor heterostructure having an active layer sandwiched between an n-type layer and a p-type layer, wherein the active layer forms a gain medium of width W. Front and back reflectors of reflectivity Rf and Rb are arranged on opposing side facets of the semiconductor heterostructure part to form a cavity of length L containing at least a part of the active layer which thus forms the gain medium for the laser diode, the gain medium having an internal loss ?i. To achieve stable, low power operation close to threshold, the laser diode is configured with the following parameter combination: width W: 1 ?m?W?2 ?m; cavity length L: 100 ?m?L?600 ?m; internal loss ?i: 0 cm?1??i?30 cm?1; back reflectivity Rb: 100?Rb?80%; and front reflectivity Rf: 100?Rf?60%.

Abstract: A low power, side-emitting semiconductor laser diode is provided. The laser diode is formed from a semiconductor heterostructure having an active layer sandwiched between an n-type layer and a p-type layer, wherein the active layer forms a gain medium of width W. Front and back reflectors of reflectivity Rf and Rb are arranged on opposing side facets of the semiconductor heterostructure part to form a cavity of length L containing at least a part of the active layer which thus forms the gain medium for the laser diode, the gain medium having an internal loss ?i. To achieve stable, low power operation close to threshold, the laser diode is configured with the following parameter combination: width W: 1 ?m?W?2 ?m; cavity length L: 100 ?m?L?600 ?m; internal loss ?i: 0 cm?1?i?30 cm?1; back reflectivity Rb: 100?Rb?80%; and front reflectivity Rf: 100?Rf?60%.

Abstract: A group III-nitride semiconductor device comprises a light emitting semiconductor structure comprising a p-type layer and an n-type layer operable as a light emitting diode or laser. On top of the p-type layer there is arranged an n+ or n++-type layer of a group III-nitride, which is transparent to the light emitted from the underlying semiconductor structure and of sufficiently high electrical conductivity to provide lateral spreading of injection current for the light-emitting semiconductor structure.