According to one aspect, the invention relates to an element for quantum photodetection of an incident radiation in a spectral band centered around a central wavelength .sub.0, having a front surface intended for receiving said radiation, and including: a stack of layers of semiconductor material forming a PN or PIN junction and including at least one layer made of an absorbent semiconductor material having a cut-off wavelength .sub.0>.sub.0, the stack of layers of semiconductor material forming a resonant optical cavity; and a structure for coupling the incident radiation with the optical cavity such as to form a resonance at the central wavelength .sub.0 allowing the absorption of more than 80% in the layer of absorbent semiconductor material at said central wavelength, and an absence of resonance at the radiative wavelength .sub.rad, wherein the radiative wavelength .sub.rad is the wavelength for which, at operating temperature, the radiative recombination rate is the highest.

According to one embodiment, a semiconductor photoreceiving device includes a substrate, a first structural layer provided on the substrate, in which light enters from the substrate side and in which a refractive index changes periodically, a semiconductor layer provided on the first structural layer and including an optical absorption layer, a reflective layer provided on the semiconductor layer, and a pair of electrodes configured to apply voltage to the optical absorption layer.

An imaging device with excellent imaging performance is provided. An imaging device that easily performs imaging under a low illuminance condition is provided. A low power consumption imaging device is provided. An imaging device with small variations in characteristics between its pixels is provided. A highly integrated imaging device is provided. A photoelectric conversion element includes a first electrode, and a first layer, a second layer, and a third layer. The first layer is provided between the first electrode and the third layer. The second layer is provided between the first layer and the third layer. The first layer contains selenium. The second layer contains a metal oxide. The third layer contains a metal oxide and also contains at least one of a rare gas atom, phosphorus, and boron. The selenium may be crystalline selenium. The second layer may be a layer of an InGaZn oxide including c-axis-aligned crystals.

A semiconductor light receiving device includes a substrate, a semiconductor fine line waveguide provided on the substrate, and a light receiving circuit that is provided on the substrate and that absorbs light propagating through the semiconductor fine line waveguide. The light receiving circuit includes a p type first semiconductor layer, a number of second semiconductor mesa structures provided on the p type first semiconductor layer in such a manner that an n type second semiconductor layer is provided on top of an i type second semiconductor layer, a p side electrode connected to the p type first semiconductor layer in a location between the second semiconductor mesa structures, and an n side electrode connected to the n type second semiconductor layer. The refractive index and the optical absorption coefficient of the second semiconductor layers are greater than the refractive index and the optical absorption coefficient of the first semiconductor layer.

There are disclosed herein various implementations of a semiconductor component with a multi-layered nucleation body and method for its fabrication. The semiconductor component includes a substrate, a nucleation body situated over the substrate, and a group III-V semiconductor device situated over the nucleation body. The nucleation body includes a bottom layer formed at a low growth temperature, and a top layer formed at a high growth temperature. The nucleation body also includes an intermediate layer that is formed substantially continuously using a varying intermediate growth temperature.

A photoelectric conversion element includes a photoelectric conversion layer having the quantum structure and utilizes intersubband transition in a conduction band. The photoelectric conversion element includes a superlattice semiconductor layer in which a barrier layer and a quantum dot layer as a quantum layer are alternately and repeatedly stacked. The barrier layer includes an indirect transition semiconductor material, and the quantum dot layer has a nano-structure including a direct transition semiconductor material. The indirect transition semiconductor material constituting the barrier layer has a bandgap of more than 1.42 eV at room temperature.

A method produces a light-receiving device by growing a light-receiving layer having an undoped multi-quantum well structure; growing a cap layer on the light-receiving layer while the cap layer is doped with a p-type impurity during its growth; growing a mesa structure; growing a protective film on surfaces of the mesa structure; and annealing to form a p-n junction. The mesa structure is defined by a surrounding trench. Alternatively, a selective growth mask can be formed on the light-receiving layer whereafter the cap layer is grown on the light-receiving layer by use of the mask. In the alternative, the p-n junction is formed by diffusing p-type impurity from a p-type contact layer of the cap layer through a concentration adjusting layer thereof to the light-receiving layer.

A semiconductor optical device includes a semiconductor substrate having first to fourth regions, a 90-degree optical hybrid provided in the third region on a principal surface of the semiconductor substrate, first and second waveguides provided in the first region and being optically coupled to the 90-degree optical hybrid, a photodiode provided in the fourth region, a third waveguide provided in the second region to optically couple the 90-degree optical hybrid to the photodiode, and a metal layer provided on a back surface of the semiconductor substrate. The metal layer includes a first part provided in the first region and a second part provided in the second region that is spaced apart from the first part by a distance. The 90-degree optical hybrid has a first length. The distance between the first and second parts is more than or equal to the first length.

Embodiments described herein relate to a dual-band photodetector. The dual-band photodetector includes a barrier layer (10) disposed between two infrared absorption layers (8, 12) wherein the barrier layer (10) is lattice matched to at least one of the infrared absorption layers (8, 12). Furthermore, one infrared absorption layer includes dilute nitride to adjust the band gap to a desired cut-off wavelength while maintaining valence-band alignment with the barrier layer. Embodiments also relate to a system and processes for producing the photodetector fabricated from semiconductor materials.

A method of forming a layered OP material is provided, where the layered OP material comprises an OPGaAs template, and a layer of GaP on the OPGaAs template. The OPGaAs template comprises a patterned layer of GaAs having alternating features of inverted crystallographic polarity of GaAs. The patterned layer of GaAs comprises a first feature comprising a first crystallographic polarity form of GaAs having a first dimension, and a second feature comprising a second crystallographic polarity form of GaAs having a second dimension. The layer of GaP on the patterned layer of GaAs comprises alternating regions of inverted crystallographic polarity that generally correspond to their underlying first and second features of the patterned layer of GaAs. Additionally, each of the alternating regions of inverted crystallographic polarity of GaP are present at about 100 micron thickness or more.