A semiconductor device comprises a substrate, one or more first III-semiconductor layers, and a plurality of superlattice structures between the substrate and the one or more first layers. The plurality of superlattice structures comprises an initial superlattice structure and one or more further superlattice structures between the initial superlattice structure and the one or more first layers. The plurality of superlattice structures is configured such that a strain-thickness product of semiconductor layer pairs in each superlattice structure of the one or more further superlattice structures is greater than or equal to a strain-thickness product of semiconductor layer pairs in superlattice structure(s) of the plurality of superlattice structures between that superlattice structure and the substrate. The plurality of superlattice structures is also configured such that a strain-thickness product of semiconductor layer pairs in at least one of the one or more further superlattice structures is greater than a strain-thickness product of semiconductor layer pairs in the initial superlattice structure.

An apparatus, a method, and an optical device for generating light. A conductive quantum well junction is positioned between a first electrode and a second electrode. The conductive quantum well junction is configured to enter into a resonant state to inelastically tunneling one or more electrons. The conductive quantum well junction may include a first dielectric layer, a third conductive layer, and a second dielectric layer. The third conductive layer may be positioned between the first dielectric layer and the second dielectric layer. The first dielectric layer may be coupled to the second electrode and the second dielectric layer is coupled to the first electrode.

A method for producing a surfaced passivated, encapsulated surface III-V type II superlattice (T2SL) photodetector, more specifically a p-type heterojunction device by cleaning, etching and exposing the surface of a III/V material to solution mixtures which simultaneously removes oxides from the surface and encapsulates the surfaces.

A method for manufacturing a semiconductor device includes selectively forming an insulating film on a region of a substrate serving as a scribe line; and forming a first semiconductor layer in a state where a cavity is provided on the insulating film. The cavity is buried in the first semiconductor layer.

A semiconductor crystal substrate includes a crystal substrate that is formed of a material including one of GaSb and InAs, a first buffer layer that is formed on the crystal substrate and formed of a material including GaSb, and a second buffer layer that is formed on the first buffer layer and formed of a material including GaSb. The first buffer layer has a p-type conductivity, and the second buffer layer has an n-type conductivity.

An infrared-ray sensing device includes a support and a plurality of photodiodes disposed on the support. Each of the plurality of photodiodes includes a first mesa including a first semiconductor layer of a first conductivity type, a second semiconductor layer of the first conductivity type, a third semiconductor layer of a second conductivity type that is disposed between the first and second semiconductor layers, and a super-lattice region disposed on the support along a reference plane. Each of the third semiconductor layer and the super-lattice region is provided in common for the photodiodes. The first mesas and the second semiconductor layers are aligned along a first axis intersecting the reference plane so that each of the second semiconductor layers is provided in a position corresponding to the position of first mesa. The second semiconductor layer is disposed between the third semiconductor layer and the super-lattice region.

A photodetector comprising a photoabsorber, comprising a doped semiconductor, a contact layer comprising a doped semiconductor and a barrier layer comprising a charge carrier compensated semiconductor, the barrier layer compensated by doping impurities such that it exhibits a valence band energy level substantially equal to the valence band energy level of the photo absorbing layer and a conduction band energy level exhibiting a significant band gap in relation to the conduction band of the photo absorbing layer, the barrier layer disposed between the photoabsorber and contact layers. The relationship between the photo absorbing layer and contact layer valence and conduction band energies and the barrier layer conduction and valance band energies is selected to facilitate minority carrier current flow while inhibiting majority carrier current flow between the contact and photo absorbing layers.

An optical device includes an active layer that includes at least two outer barriers and at least one coupled quantum well that is inserted between the at least two outer barriers. Each coupled quantum well includes at least three quantum well layers and at least two coupling barriers that are respectively provided between the at least three quantum well layers. Thicknesses of two quantum well layers disposed at opposite end portions of the at least three quantum well layers are less than a thickness of the other quantum well layer disposed between the two quantum well layers disposed at the opposite end portions. A bandgap of the two quantum well layers disposed at the opposite end portions may be higher than a bandgap of the other quantum well layer disposed between the two quantum well layers.

Resonant-cavity infrared photodetector (RCID) devices that include a thin absorber layer contained entirely within the resonant cavity. In some embodiments, the absorber region is a single type-II InAs—GaSb interface situated between an n-type region comprising an AlSb/InAs n-type superlattice and a p-type AlSb/GaSb region. In other embodiments, the absorber region comprises one or more quantum wells formed on an upper surface of the n-type region. In other embodiments, the absorber region comprises a “W”-structured quantum well situated between two barrier layers, the “W”-structured quantum well comprising a hole quantum well sandwiched between two electron quantum wells. In other embodiments, an RCID in accordance with the present invention includes a thin absorber region and an nBn or pBp active core within a resonant cavity.

An improved heterostructure for an optoelectronic device is provided. The heterostructure includes an active region, an electron blocking layer, and a p-type contact layer. The electron blocking layer is located between the active region and the p-type contact layer. In an embodiment, the electron blocking layer can include a plurality of sublayers that vary in composition.