Semiconductor optoelectronic devices having a dilute nitride active region are disclosed. In particular, the semiconductor devices have a dilute nitride active region with at least two bandgaps within a range from 0.7 eV and 1.4 eV. Photodetectors comprising a dilute nitride active region with at least two bandgaps have a reduced dark current when compared to photodetectors comprising a dilute nitride active region with a single bandgap equivalent to the smallest bandgap of the at least two bandgaps.

Avalanche photodetector devices and methods of use thereof are provided that incorporate deep levels to increase secondary carrier generation via impact ionization under application of a reverse bias. An avalanche photodetector device may include p+ and n+ regions, an intermediate semiconductor absorption region provided therebetween, and at least one semiconductor region residing between the p+ and n+ regions that incorporates deep levels. When light is incident on the device such that the absorption depth of the light extends into the intermediate semiconductor absorption region, a photocurrent is produced under a reverse bias includes both photocarriers generated within the intermediate semiconductor absorption region and secondary carriers released from the deep levels via impact ionization. The deep levels may facilitate an increased sensitivity, relative to a device absent of deep levels, via a deep-level ionization energy threshold that is less than a threshold for conventional impact ionization across a bandgap.

Semiconductor optoelectronic devices having a dilute nitride active region are disclosed. In particular, the semiconductor devices have a dilute nitride active region with at least two bandgaps within a range from 0.7 eV and 1.4 eV. Photodetectors comprising a dilute nitride active region with at least two bandgaps have a reduced dark current when compared to photodetectors comprising a dilute nitride active region with a single bandgap equivalent to the smallest bandgap of the at least two bandgaps.

A device for detecting a chemical species, including a Geiger-mode avalanche diode, which includes a body of semiconductor material delimited by a front surface. The semiconductor body includes: a cathode region having a first type of conductivity, which forms the front surface; and an anode region having a second type of conductivity, which extends in the cathode region starting from the front surface. The detection device further includes: a sensitive structure arranged on the anode region and including at least one sensitive region, which has an electrical permittivity that depends upon the concentration of the chemical species; and a resistive region, arranged on the sensitive structure and electrically coupled to the anode region.

Avalanche photodetector devices are disclosed in which spatial asymmetry is employed to preferentially enhance avalanche multiplication of electrons. In some example embodiments, an avalanche photodetector device includes p-doped and n-doped regions and a central waveguide region, where the p-doped region is laterally offset from the central waveguide by a first lateral offset region, and where the n-doped region is laterally offset from the central waveguide by a second lateral offset region. The first and second lateral offset regions are asymmetrically defined such that impact ionization and avalanche multiplication of electrons in the second laterally offset region is enhanced relative to that of holes in the first laterally offset region. In some example implementations, the asymmetry may be provided by a difference in relative heights and/or lateral spatial extends (widths) of the lateral offset regions, such that the electric field, or a spatial extent associated therewith, is enhanced for electrons.

Provided are a photodetector, a manufacturing method thereof, and a lidar system. A photosensitive region of the photodetector is circular and has a diameter range of 100-300 μm. Compared with a conventional photodetector having a photosensitive region with a diameter of 50 μm, the photodetector of the present invention can have a detection range greater than 200 m, responsivity greater than 20 A/W and a dark current less than 10 nA.

Provided are an infrared detecting device and an infrared detecting system including the infrared detecting device. The infrared detecting device includes at least one infrared detector, and the at least one infrared detector includes a substrate, a buffer layer, and at least one light absorbing portion. The buffer layer includes a superlattice structure.

The present disclosure relates to semiconductor structures and, more particularly, to photodiodes and/or PIN diode structures and methods of manufacture. The structure includes: at least one fin including substrate material, the at least one fin including sidewalls and a top surface; a trench on opposing sides of the at least one fin; a first semiconductor material lining the sidewalls and the top surface of the at least one fin, and a bottom surface of the trench; a photosensitive semiconductor material on the first semiconductor material and at least partially filling the trench; and a third semiconductor material on the photosensitive semiconductor material.

Through selective incorporation of high carrier mobility graphene monolayers into low cost, NIR-sensitive SiGe detector layer structures, a device combining beneficial features from both technologies can be achieved. The SiGe in such hybrid SiGe/graphene detector devices serves as the NIR absorbing layer, or as the quantum dot material in certain device iterations. The bandgap of this SiGe layer where absorption of photons and photogeneration of carriers mainly takes place may be tuned by varying the concentrations of Ge in the SixGe1-x material. This bandgap and the thickness of this layer largely impact the degree and spectral characteristics of absorption properties, and thus the quantum efficiency or responsivity of the device. The main function and utility of the graphene monolayers, which are nearly transparent to incident light, is to facilitate the extraction and transport of electron and hole carriers from the SiGe absorbing layer through the device.

A directional photodetector comprises a photosensitive element and a light selector. The photosensitive element comprises a single-photon avalanche diode, SPAD, or an array of SPADs or SPAD array. The light selector is arranged on or above the photosensitive element, in particular on or above an active surface of the photosensitive element. The light selector is configured to restrict a field of view of the photosensitive element at least for light with a wavelength within a specified wavelength range. The light selector is configured to restrict the field of view by predominantly passing light with a direction of incidence within a range of passing directions of the light selector.