Example embodiments relate to controlling detection time in photodetectors. An example embodiment includes a device. The device includes a substrate. The device also includes a photodetector coupled to the substrate. The photodetector is arranged to detect light emitted from a light source that irradiates a top surface of the device. A depth of the substrate is at most 100 times a diffusion length of a minority carrier within the substrate so as to mitigate dark current arising from minority carriers photoexcited in the substrate based on the light emitted from the light source.

An image sensor with embedded wells for accommodating light emitters includes a semiconductor substrate including an array of doped sensing regions respectively corresponding to an array of photosensitive pixels of the image sensor. The semiconductor substrate forms an array of wells. Each well is aligned with a respective doped sensing region to facilitate detection, by the photosensitive pixel that includes said respective doped sensing region, of light emitted to the photosensitive pixel by a light emitter disposed in the well. The image sensor further includes, between adjacent doped sensing regions, a light-blocking barrier to reduce propagation of light to the doped sensing-region of each photosensitive pixel from wells not aligned therewith.

Techniques for enhancing the absorption of photons in semiconductors with the use of microstructures are described. The microstructures, such as pillars and/or holes, effectively increase the effective absorption length resulting in a greater absorption of the photons. Using microstructures for absorption enhancement for silicon photodiodes and silicon avalanche photodiodes can result in bandwidths in excess of 10 Gb/s at photons with wavelengths of 850 nm, and with quantum efficiencies of approximately 90% or more.

The present disclosure relates to an image sensor including a pixel along a substrate. The pixel includes a first semiconductor region having a first doping type. A second semiconductor region is directly over the first semiconductor region. The second semiconductor region has a second doping type opposite the first doping type and meets the first semiconductor region at a p-n junction. A ring-shaped third semiconductor region laterally surrounds the first and second semiconductor regions. The ring-shaped third semiconductor region has the first doping type. A ring-shaped fourth semiconductor region laterally surrounds the ring-shaped third semiconductor region. The ring-shaped fourth semiconductor region has the second doping type. A ring-shaped fifth semiconductor region is directly over the ring-shaped third semiconductor region and has the second doping type.

A method includes providing a semiconductor substrate having a front side surface and a back side surface opposite to the front side surface. A photosensitive region of the semiconductor substrate is etched to form a recess. A semiconductor material is deposited on the semiconductor substrate to form a radiation sensing member filling the recess. The semiconductor material has an optical band gap energy smaller than 1.77 eV. A device layer is formed over the front side surface of the semiconductor substrate and the radiation sensing member. A trench isolation is formed in an isolation region of the semiconductor substrate and extending from the back side surface of the semiconductor substrate.

An optical sensing apparatus is provided. The optical sensing apparatus includes a substrate, one or more pixels supported by the substrate, where each of the one or more pixels includes an absorption region, a field control region, a first contact region, a second contact region and a carrier confining region. The field control region and the first contact region are doped with a dopant of a first conductivity type. The second contact region is doped with a dopant of a second conductivity type. The carrier confining region includes a first barrier region and a channel region, where the first barrier region is doped with a dopant of the second conductivity type and has a first peak doping concentration, and where the channel region is intrinsic or doped with a dopant of the second conductivity type and has a second peak doping concentration lower than the first peak doping concentration.

A waveguide photodetector includes a first contact layer of a first conductivity type, a waveguide layer, and a second contact layer of a second conductivity type that are sequentially formed on the semiconductor substrate. The waveguide layer includes a first cladding layer of the first conductivity type disposed on a side of the first contact layer, a second cladding layer of the second conductivity type disposed on a side of the second contact layer, and the core layer disposed between the first cladding layer and the second cladding layer. The core layer includes a light absorption layer and an impurity-doped light absorption layer that has a higher concentration of a p-type impurity than that of the light absorption layer and is disposed on a side of a light incident face.

A photoelectric conversion module (10) comprises a photoelectric conversion cell (12) and a grid electrode (31) provided in the photoelectric conversion cell (12) on a substrate. The photoelectric conversion cell (12) includes a first electrode layer (22), a second electrode layer (24), a photoelectric conversion layer (26) between the first electrode layer (22) and the second electrode layer (24). The second electrode layer (24) is formed of a transparent electrode layer located on opposite side of the photoelectric conversion layer (26) to the substrate (20). The grid electrode (31) is provided between the photoelectric conversion layer (26) and the transparent electrode layer.

A light sensitive semiconductor structure comprises: a substrate; a doped upper region of said substrate having a first type of doping; a first implant region located below and being in direct contact with said doped upper region, said first implant region having a second type of doping so that a pn-junction is located between said doped upper region and said first implant region; and a second implant region located below said first implant region and having said second type of doping, and wherein a peak in a doping profile of said second type of doping is located in said second implant region.

A light sensing device including a first conductivity type buried layer, a second conductivity type well, and a first conductivity type well is provided. The second conductivity type well is on the first conductivity type buried layer. The first conductivity type well is on the second conductivity type well and surrounded by the second conductivity type well.