A quantum cascade laser includes a substrate having a group III-V compound semiconductor and a core region that is provided on the substrate and that includes a group III-V compound semiconductor. The core region includes a plurality of unit structures that are stacked on top of one another. Each of the plurality of unit structures includes an active layer and an injection layer. The injection layer includes at least one strain-compensated layer including a first well layer and a first barrier layer and at least one lattice-matched layer including a second well layer and a second barrier layer. The first well layer has a lattice constant larger than a lattice constant of the substrate. The first barrier layer has a lattice constant smaller than the lattice constant of the substrate. The second well layer and the second barrier layer each have a lattice constant that is lattice-matched to the substrate.

A semiconductor device comprising a silicon substrate on which is grown a <100 nm thick epilayer of AlAs or related compound, followed by a compound semiconductor other than GaN buffer layer. Further III-V compound semiconductor structures can be epitaxially grown on top. The AlAs epilayer reduces the formation and propagation of defects from the interface with the silicon, and so can improve the performance of an active structure grown on top.

A semiconductor laser may include a substrate, an active region, and an electron stopper layer. The electron stopper layer may include an aluminum gallium indium arsenide phosphide alloy. The aluminum gallium indium arsenide phosphide alloy may have an Al.sub.xGa.sub.yIn.sub.(1-x-y)As.sub.zP.sub.(1-z) composition.

The present invention proposes an O-band silicon-based high-speed semiconductor laser diode for optical communication and its manufacturing method, by using different buffer layers to form the growth surface of InP material with low dislocation density; N—InAlGaAs is used instead of conventional N—InAlAs electron-blocking layer in the epi-structure to reduce the barrier for electrons to enter the quantum wells from N-type and lower the threshold; a superlattice structure quantum barrier is used instead of a single layer barrier structure to improve the transport of heavy holes in the quantum wells; and the material structure is adjusted to achieve a reliable O-band high direct modulation speed semiconductor laser diode for optical communication on silicon substrate.

A photonic integrated circuit device includes a passive waveguide section formed over a substrate, a quantum cascade laser (QCL) gain section formed over the substrate and adjacent to the passive waveguide section, and a taper section disposed between and in contact with each of the passive waveguide section and the QCL gain section. In some embodiments, the passive waveguide section includes a passive waveguide core layer disposed between a first cladding layer and a second cladding layer. In some examples, the QCL gain section includes a QCL active region disposed between a first confinement layer and a second confinement layer, where the QCL active region has a lower index of refraction than each of the first and second confinement layers. In some embodiments, the taper section is configured to optically couple the QCL gain section to the passive waveguide section.

Semiconductor devices, such as vertical-cavity surface-emitting lasers, and methods for manufacturing the same, are disclosed. The semiconductor devices include contact extensions and electrically conductive adhesive material, such as fusible metal alloys or electrically conductive composites. In some instances, the semiconductor devices further include structured contacts. These components enable the production of semiconductor devices having minimal distortion. For example, arrays of vertical-cavity surface-emitting lasers can be produced exhibiting little to no bowing. Semiconductor devices having minimal distortion exhibit enhanced performance in some instances.

An optical device has a gallium and nitrogen containing substrate including a surface region and a strain control region, the strain control region being configured to maintain a quantum well region within a predetermined strain state. The device also has a plurality of quantum well regions overlying the strain control region.

An optical device has a gallium and nitrogen containing substrate including a surface region and a strain control region, the strain control region being configured to maintain a quantum well region within a predetermined strain state. The device also has a plurality of quantum well regions overlying the strain control region.

Systems and methods are described herein to grow a layered structure. The layered structure is implemented as a VCSEL and comprises a first germanium substrate layer having a first lattice constant, a second layer that has a second lattice constant and is epitaxially grown over the first germanium substrate layer, wherein the second layer comprises a compound of a first constituent and a second constituent, and a third layer that has a third lattice constant and is epitaxially grown over the second layer, wherein the third layer comprises a compound of a third constituent and a fourth constituent, wherein the first, second, third and fourth constituents are selected such that the layered structure is pseudomorphic and the first lattice constant is between the second lattice constant and the third lattice constant.

A quantum cascade laser includes a substrate having a group III-V compound semiconductor and a core region that is provided on the substrate and that includes a group III-V compound semiconductor. The core region includes a plurality of unit structures that are stacked on top of one another. Each of the plurality of unit structures includes an active layer and an injection layer. The injection layer includes at least one strain-compensated layer including a first well layer and a first barrier layer and at least one lattice-matched layer including a second well layer and a second barrier layer. The first well layer has a lattice constant larger than a lattice constant of the substrate. The first barrier layer has a lattice constant smaller than the lattice constant of the substrate. The second well layer and the second barrier layer each have a lattice constant that is lattice-matched to the substrate.