A detector (10) that detects light (237) includes a sensor array (232) having a plurality of pixels (234). Each pixel (234) can include a first pixel layer (236A), and a second pixel layer (236B) stacked on top of the first pixel layer (236A). The first pixel layer (236A) can include a first, fast conductor electrode (238A) and a plurality of first quantum dots (240A) that absorb light (237) in a first range of wavelengths. The second pixel layer (236B) can include a second, fast conductor electrode (238B) and a plurality of second quantum dots (240B) that absorb light (237) in a second range of wavelengths. The second range of wavelengths is higher energy than the first range of wavelengths.

A light detecting device includes: an optical filter (2) that transmits a first wavelength light having a wavelength in a first wavelength range, a second wavelength light having a wavelength in a second wavelength range, . . . , and an n-th wavelength light having a wavelength in an n-th wavelength range (n is an integer); an optical sensor (3) that detects at least one of a first wavelength light intensity of the first wavelength light, a second wavelength light intensity of the second wavelength light, . . . , and an n-th wavelength light intensity of the n-th wavelength light; and an analysis unit (4) that estimates a light intensity of light having a wavelength in a wavelength range other than at least one of the first wavelength range, the second wavelength range, . . . , and the n-th wavelength range based on at least one of the first wavelength light intensity, the second wavelength light intensity, . . . , and the n-th wavelength light intensity. A correlative relationship exists between a light intensity of light having a wavelength in the at least one wavelength range and the light intensity of the light having the wavelength in the wavelength range other than the at least one wavelength range.

A three-dimensional multispectral imaging sensor and method for forming a three-dimensional multispectral imaging sensor are provided. The three-dimensional multispectral imaging sensor includes a monolithic structure having a plurality of layers. Each of the layers is formed from light detecting materials for detecting light of respective different non-overlapping wavelengths and having respective different bandgaps

The present application relates to a photodetector based on interband transition in quantum wells. The photodetector may include a first semiconductor layer having a first conduction type; a second semiconductor layer having a second conduction type different from the first conduction type; and a photon absorption layer arranged between the first semiconductor layer and the second semiconductor layer, the photon absorption layer including at least one quantum well layer and barrier layers arranged on both sides of each quantum well layer. The present application utilizes the modulating effect of a semiconductor PN junction on a photoelectric conversion process associated with quantum wells to significantly increase a current output of the photodetector based on the quantum well material.

A radiation detector is provided that includes a photodiode having a radiation absorber with a graded multilayer structure. Each layer of the absorber is formed from a semiconductor material, such as HgCdTe. A first of the layers is formed to have a first predetermined wavelength cutoff. A second of the layers is disposed over the first layer and beneath the first surface of the absorber through which radiation is received. The second layer has a graded composition structure of the semiconductor material such that the wavelength cutoff of the second layer varies from a second predetermined wavelength cutoff to the first predetermined wavelength cutoff such that the second layer has a progressively smaller bandgap than the first bandgap of the first layer. The graded multilayer radiation absorber structure enables carriers to flow toward a conductor that is used for measuring the radiation being sensed by the radiation absorber.

Methods, devices, and systems for optical sensing are provided. In one aspect, an optical sensing apparatus includes: a first absorption region configured to absorb light in at least a first spectrum with visible or near infrared wavelengths; a second absorption region formed over the first absorption region, the second absorption region configured to absorb light in at least a second spectrum with near infrared or shortwave infrared wavelengths; and a third absorption region formed over the second absorption region, the third absorption region configured to absorb light in at least a third spectrum with shortwave infrared or mid-wave infrared wavelengths.

Disclosed herein is an infrared detector. The detector includes a plurality of pixels. Each pixel includes an n-type semiconductor top contact layer, a p-type semiconductor layer electrically connected to the n-type top contact layer to form a top p-n junction, a unipolar electron barrier electrically connected to the p-type semiconductor layer, a bottom absorber, and an n-type semiconductor bottom contact layer electrically connected to the bottom absorber. The unipolar electron barrier is positioned between the p-type semiconductor layer and the bottom absorber.

This invention includes quantum dot channel (QDC) Si FETs, which detect infrared radiation to serve as photodetectors. GeOx-cladded Ge quantum dots form the quantum dot channel. An assembly of cladded quantum dots, such as Ge and Si, with thin barrier layers (GeOx and SiOx) form a quantum dot superlattice (QDSL). A QDSL exhibits narrow energy widths of sub-bands (or mini-energy bands) with sub-bands separation ranging 0.2-0.5 eV. The energy separation depends on the barrier thickness (0.5-1 nm) and diameter of quantum dots (3-5 nm). Drain current magnitude in a QDSL layer or quantum dot channel depends on density of electrons in the QD inversion channel, which in turn depends on number of sub-bands participating in the conduction for a given drain voltage VD and gate voltage VG. Infrared photons with energy corresponding to the intra sub-band separation are absorbed as electrons in a lower sub-band make transition to the upper sub-band.

A CMOS image sensor includes: a substrate containing a potential well stack including: a first p-well, a first n-well disposed below the first p-well, a second p-well disposed below the first n-well, a second n-well disposed below the second p-well, and a third p-well disposed below the second n-well, wherein a first photodiode is formed at the junction between the first p-well and first n-well, a second photodiode is formed at the junction between the first n-well and second p-well, a third photodiode is formed at the junction between the second p-well and the second n-well, and a fourth photodiode is formed at the junction between the second n-well and the third p-well, and each photodiode is disposed at a different respective depth within the substrate; and a plurality of active pixel sensors for converting light received by the photodiodes into electrical charge.

An electromagnetic radiation spectrum detection system including a sensor device and an electronic control and processing module. The sensor device may include two photodiodes. The sensor device may convert an incident electromagnetic radiation (EMR) into electrical current. The electronic control and processing module may store numerical calibration values representative of a responsivity matrix of the sensor device. The electronic control and processing module may selectively provide the sensor device with electrical control voltage values (V.sub.B). The electronic control and processing module may process the values of detected electric currents (Iph) and the numerical calibration values to obtain spectrum information related to incident electromagnetic radiation spectrums. The electronic control and processing module may determine power spectral density of incident electromagnetic radiation.