Abstract: Subwells are added to quantum wells of light emitting semiconductor structures to shift their emission wavelengths to longer wavelengths. Typical applications of the invention are to InGaAs, InGaAsSb, InP and GaN material systems, for example.

Abstract: Embodiments of the invention provide for improved separation of switching material by creating a diversion of the activating force. In one embodiment at least one structural element is positioned in close proximity to an inlet for the actuating force to influence the actuating force to fully separate the switching material. Structural elements may include protrusions, either adjacent to the inlet or approximately across the channel from the inlet, as well as at least one additional inlet. The diversion can be created, if desired, by forces coming from opposite sides. Embodiments of the invention make use of non-wettable surfaces lining the channel in regions where switching material is to break into separate volumes, and wettable surfaces away from such regions. Embodiments of the invention provide for multi-pole, multi-throw switching.

Abstract: The method comprises forming barrier layers of AlxGa1-xAs, forming a quantum well layer of InGaAs between the barrier layers, and forming an interfacial layer between the quantum well layer and each of the barrier layers.

Abstract: Double well structures in electro-absorption modulators are created in quantum well active regions by embedding deep ultra thin quantum wells. The perturbation introduced by the embedded, deep ultra thin quantum well centered within a conventional quantum well lowers the confined energy state for the wavefunction in the surrounding larger well and typically results in the hole and electron distributions being more confined to the center of the conventional quantum well. The extinction ratio provided by the electro-absorption modulator is typically increased.

Abstract: In accordance with the invention, increased maximum modulation speeds and improved hole distribution are obtained for light emitting devices. Barrier layers of a quantum well structure for a light emitting device are formed with varying barrier energy heights. Quantum well layers of the quantum well structure are formed between the barrier layers.

Abstract: 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.

Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.

Abstract: The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III–V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 ?m is deposited over the substrate wafer.

Abstract: Subwells are added to quantum wells of light emitting semiconductor structures to shift their emission wavelengths to longer wavelengths. Typical applications of the invention are to InGaAs, InGaAsSb, InP and GaN material systems, for example.

Abstract: The light-emitting device comprises a substrate, an active region and a tunnel junction structure. The substrate comprises gallium arsenide. The active region comprises an n-type spacing layer and a p-type spacing layer. The tunnel junction structure comprises a p-type tunnel junction layer adjacent the p-type spacing layer, an n-type tunnel junction layer and a tunnel junction between the p-type tunnel junction layer and the n-type tunnel junction layer. The p-type tunnel junction layer comprises a layer of a p-type first semiconductor material that includes gallium and arsenic. The n-type tunnel junction layer comprises a layer of an n-type second semiconductor material that includes indium, gallium and phosphorus. The high dopant concentration attainable in the second semiconductor material reduces the width of the depletion region at the tunnel junction and increases the electrostatic field across the tunnel junction, so that the reverse bias at which tunneling occurs is reduced.

Abstract: The method comprises forming barrier layers of AlxGa1-xAs, forming a quantum well layer of InGaAs between the barrier layers, and forming an interfacial layer between the quantum well layer and each of the barrier layers.

Abstract: A strain compensating structure comprises a strain compensating layer adjacent an oxide-forming layer. The strain compensating layer compensates for the change in the lattice parameter due to oxidation of at least part of the oxide-forming layer.

Abstract: A laser and method for making the same are disclosed. The laser includes a p-layer, an n-layer, and an active region located between the p-layer and the n-layer. The active region includes a quantum well layer sandwiched between first and second barrier layers. The quantum well layer includes an InP-based material. The first and second barrier layers also include an InP-based material. The barrier layers are homogeneous layers of the InP-based material. The barrier layers are preferably deposited by chemical vapor deposition from precursors that include a surfactant element that inhibits the formation of P—P dimers on a surface of the barrier layer during the deposition process. In one embodiment, the surfactant element is chosen from the group consisting of Sb, Si, and Te, and the barrier material includes InGaP or AlInP.

Abstract: 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.

Abstract: The light-emitting device comprises a substrate, an active region and a tunnel junction structure. The substrate comprises gallium arsenide. The active region comprises an n-type spacing layer and a p-type spacing layer. The tunnel junction structure comprises a p-type tunnel junction layer adjacent the p-type spacing layer, an n-type tunnel junction layer and a tunnel junction between the p-type tunnel junction layer and the n-type tunnel junction layer. The p-type tunnel junction layer comprises a layer of a p-type first semiconductor material that includes gallium and arsenic. The n-type tunnel junction layer comprises a layer of an n-type second semiconductor material that includes indium, gallium and phosphorus. The high dopant concentration attainable in the second semiconductor material reduces the width of the depletion region at the tunnel junction and increases the electrostatic field across the tunnel junction, so that the reverse bias at which tunneling occurs is reduced.

Abstract: The active region of a long-wavelength light emitting device is made by providing an organometallic vapor phase epitaxy (OMVPE) reactor, placing a substrate wafer capable of supporting growth of indium gallium arsenide nitride in the reactor, supplying a Group III-V precursor mixture comprising an arsenic precursor, a nitrogen precursor, a gallium precursor, an indium precursor and a carrier gas to the reactor and pressurizing the reactor to a sub-atmospheric elevated growth pressure no higher than that at which a layer of indium gallium arsenide layer having a nitrogen fraction commensurate with light emission at a wavelength longer than 1.2 &mgr;m is deposited over the substrate wafer.

Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.

Abstract: A laser and method for making the same are disclosed. The laser includes a p-layer, an n-layer, and an active region located between the p-layer and the n-layer. The active region includes a quantum well layer sandwiched between first and second barrier layers. The quantum well layer includes an InP-based material. The first and second barrier layers also include an InP-based material. The barrier layers are homogeneous layers of the InP-based material. The barrier layers are preferably deposited by chemical vapor deposition from precursors that include a surfactant element that inhibits the formation of P-P dimers on a surface of the barrier layer during the deposition process. In one embodiment, the surfactant element is chosen from the group consisting of Sb, Si, and Te, and the barrier material includes InGaP or AlInP.

Abstract: The tunnel junction structure comprises a p-type tunnel junction layer of a first semiconductor material, an n-type tunnel junction layer of a second semiconductor material and a tunnel junction between the tunnel junction layers. At least one of the semiconductor materials includes gallium (Ga), arsenic (As) and either nitrogen (N) or antimony (Sb). The probability of tunneling is significantly increased, and the voltage drop across the tunnel junction is consequently decreased, by forming the tunnel junction structure of materials having a reduced difference between the valence band energy of the material of the p-type tunnel junction layer and the conduction band energy of the n-type tunnel junction layer.

Abstract: Several methods for producing an active region for a long wavelength light emitting device are disclosed. In one embodiment, the method comprises placing a substrate in an organometallic vapor phase epitaxy (OMVPE) reactor, the substrate for supporting growth of an indium gallium arsenide nitride (InGaAsN) film, supplying to the reactor a group-III-V precursor mixture comprising arsine, dimethylhydrazine, alkyl-gallium, alkyl-indium and a carrier gas, where the arsine and the dimethylhydrazine are the group-V precursor materials and where the percentage of dimethylhydrazine substantially exceeds the percentage of arsine, and pressurizing the reactor to a pressure at which a concentration of nitrogen commensurate with light emission at a wavelength longer than 1.2 um is extracted from the dimethylhydrazine and deposited on the substrate.