摘要:
A semiconductor laser is formed of gallium nitride series compound semiconductor and has a double hetero structure including an MQW (multiple quantum well) active layer held between p-type and n-type AlGaN clad layers. The double hetero structure is held between p-type and n-type contact layers. An InGaN optical absorption layer having an optical absorption coefficient larger than the clad layer which has the same conductivity type as the contact layer and is formed adjacent to the contact layer is formed in at least one of the contact layers and an InAlGaN optical guided mode control layer (layer of small refractive index) having an refractive index smaller than the clad layer is formed on the exterior of the optical absorption layer.
摘要:
A gallium nitride-based compound semiconductor laser has a double-heterojunction structure, in which an active layer is sandwiched between cladding layers, on a sapphire substrate. A GaN current blocking layer having a striped opening portion is formed on the p-cladding layer. A p-GaN buried layer and a contact layer through which a current is injected into the opening portion of the current blocking layer and which are larger in area than the opening portion are formed. The active layer has a multiple quantum well structure constituted by a cyclic structure formed by cyclically stacking two types of InGaAlN layers which have different band gaps and are 10 nm or more thick.
摘要:
A semiconductor laser is formed from a gallium nitride-based compound semiconductor material, and has a double-heterostructure portion obtained by sandwiching an active layer between an n-type cladding layer and a p-type cladding layer on a sapphire substrate. The double-heterostructure portion is formed into a mesa shape on the sapphire substrate via a GaN buffer layer. The two sides of this mesa structure are buried with GaN current blocking layers.
摘要:
A gallium nitride-based compound semiconductor laser has a double-heterojunction structure, in which an active layer is sandwiched between cladding layers, on a sapphire substrate. A GaN current blocking layer having a striped opening portion is formed on the p-cladding layer. A p-GaN buried layer and a contact layer through which a current is injected into the opening portion of the current blocking layer and which are larger in area than the opening portion are formed. The active layer has a multiple quantum well structure constituted by a cyclic structure formed by cyclically stacking two types of InGaAlN layers which have different band gaps and are 10 nm or less thick.
摘要:
A gallium nitride-based compound semiconductor laser has a double-heterojunction structure, in which an active layer is sandwiched between cladding layers, on a sapphire substrate. A GaN current blocking layer having a striped opening portion is formed on the p-cladding layer. A p-GaN buried layer and a contact layer through which a current is injected into the opening portion of the current blocking layer and which are larger in area than the opening portion are formed. The active layer has a multiple quantum well structure constituted by a cyclic structure formed by cyclically stacking two types of InGaAlN layers which have different band gaps and are 10 nm or more thick.
摘要:
A light-emitting device is provided, which includes a substrate having a plane surface, a semiconductor light-emitting element mounted on the plane surface of the substrate and which emits light in a range from ultraviolet ray to visible light, a first light transmissible layer formed above the substrate and covering the semiconductor light-emitting element, a phosphor layer formed above the first light transmissible layer and containing phosphor particles and matrix, and a second light transmissible layer formed above the phosphor layer and contacting with the plane surface of the substrate. The surface of the phosphor layer has projections reflecting shapes of the phosphor particles.
摘要:
A light-emitting device is provided, which includes a substrate having a plane surface, a semiconductor light-emitting element mounted on the plane surface of the substrate and which emits light in a range from ultraviolet ray to visible light, a first light transmissible layer formed above the substrate and covering the semiconductor light-emitting element, a phosphor layer formed above the first light transmissible layer and containing phosphor particles and matrix, and a second light transmissible layer formed above the phosphor layer and contacting with the plane surface of the substrate. The surface of the phosphor layer has projections reflecting shapes of the phosphor particles.
摘要:
A semiconductor light emitting element includes a semiconductor light emitting element emitting light beams in ultraviolet ranges and visible ranges, and a fluorescent element absorbing the light beams from the semiconductor light emitting element and outputting visible light beams in a light taking-out direction different from a light emitting direction. The light beams emitted from the light emitting element is absorbed within the semiconductor light emitting device.
摘要:
A semiconductor light emitting element includes a semiconductor light emitting element emitting light beams in ultraviolet ranges and visible ranges, and a fluorescent element absorbing the light beams from the semiconductor light emitting element and outputting visible light beams in a light taking-out direction different from a light emitting direction. The light beams emitted from the light emitting element are absorbed within the semiconductor light emitting device.
摘要:
In a nitride compound semiconductor laser including an active layer sandwiched by semiconductor layers of different conduction types on a sapphire substrate, layers of polyimide for current blocking and light confinement are formed on side surfaces of a mesa-type current confining structure with and under the p-side electrode. The laser ensures efficient, uniform carrier injection into the active layer, suppresses higher-order modes other than the fundamental transverse mode, and thereby promises a high reliability ensuring continuous pulsation under a low threshold current and a low operation voltage with low noise characteristics.