An image sensor may include a substrate including first and second surfaces opposite to each other and including a single crystalline layer, a first epitaxial layer, and a second epitaxial layer sequentially stacked from the second surface. The single crystalline layer and the second epitaxial layer may be doped with first impurities of a first conductivity type. The first epitaxial layer may be doped with second impurities of a second conductivity type. A pixel separation structure extends from the first surface to penetrate at least the second and first epitaxial layers and divides the substrate into a plurality of pixels. A transfer gate electrode extends from the first surface to penetrate the second epitaxial layer. A doping concentration of the first impurities doped in the single crystalline layer may be higher than that in the second epitaxial layer.

An imaging device including: a first imaging cell including a first photoelectric converter that generates a first signal; and a second imaging cell including: a second photoelectric converter that generates a second signal; and a capacitor having a first and second terminal, the first terminal electrically coupled to second photoelectric converter. An area of the first photoelectric converter is greater than an area of the second photoelectric converter in a plan view, the first imaging cell has a first number of saturation charges, and the second imaging cell has a second number of saturation charges, the first number of saturation charges is greater than the second number of saturation charges, and the capacitor has capacitance that causes the second number of saturation charges of the second imaging cell to become greater than the first number of saturation charges of the first imaging cell.

A pixel includes a workpiece having a protrusion and a bulk, wherein the protrusion extends from an upper surface of the bulk. The pixel further includes a floating diffusion node in the protrusion. The pixel further includes a gate structure over the bulk, wherein a top surface of the gate structure is above a top surface of the floating diffusion node. The pixel further includes a photosensitive device in the bulk. The pixel further includes an isolation well surrounding the photosensitive device.

A solid-state imaging device includes a photoelectric converter, a transfer gate transistor, and an overflow gate transistor. The photoelectric converter is provided in a semiconductor substrate and generates photocharge. The transfer gate transistor is provided at a surface of the semiconductor substrate as a vertical transistor and reads the photocharge stored in the photoelectric converter. The overflow gate transistor is provided at the surface of the semiconductor substrate as a planar transistor and transfers the photocharge overflowing from the photoelectric converter.

An image sensing device includes a photoelectric conversion element, a floating diffusion (FD) region, and a transfer gate. The photoelectric conversion element is disposed in a substrate, and generates photocharges in response to incident light. The floating diffusion (FD) region is disposed over the photoelectric conversion element, and stores the photocharges generated by the photoelectric conversion element. The transfer gate transfer the photocharges generated by the photoelectric conversion element to the floating diffusion (FD) region in response to a transmission signal. The transfer gate includes a horizontal gate disposed over the photoelectric conversion element, and a vertical gate coupled to the horizontal gate. The vertical gate is positioned at a side of the photoelectric conversion element, and surrounds the photoelectric conversion element.

Aspects of the technology described herein relate to improved semiconductor-based image sensor designs. In some embodiments, an integrated circuit may comprise a photodetection region and a drain region electrically coupled to the photodetection region, and the photodetection region may be configured to induce an intrinsic electric field in a direction from the photodetection region to the drain region(s). In some embodiments, an integrated circuit may comprise a plurality of pixels and a control circuit configured to control a transfer of charge carriers in a plurality of time-binning pixels. In some embodiments, an optical component for optical rejection is provided in between a waveguide and the time-binning pixel and configured to block at least some excitation photons in a pulsed light stream from arriving at the photodetection region. In some embodiments, the time-binning pixel does not comprise a time-gated transistor for electronic rejection configured to block a transfer of charge carriers associated with excitation photons in the pulsed light stream.

Transistors include trenches formed in the semiconductor substrate having a first conductive type. The trenches define, in a channel width plane of the transistor, at least one nonplanar substrate structure having a plurality of sidewall portions and a tip portion disposed between the plurality of sidewall portions. An epitaxial overlayer is epitaxially grown on the sidewall portions and the tip portion. A channel doping layer having a doped portion of the semiconductor substrate is formed in the nonplanar substrate structure and enclosed by the epitaxial overlayer. An isolation layer is disposed in the trenches and over the epitaxial overlayer. A gate is disposed on the isolation layer and extends into the trenches.

An imaging element has at least a photoelectric conversion section, a first transistor TR.sub.1, and a second transistor TR.sub.2, the photoelectric conversion section includes a photoelectric conversion layer 13, a first electrode 11, and a second electrode 12, the imaging element further has a first photoelectric conversion layer extension section 13A, a third electrode 51, and a fourth electrode 51C, the first transistor TR.sub.1 includes the second electrode 12 that functions as one source/drain section, the third electrode that functions as a gate section 51, and the first photoelectric conversion layer extension section 13A that functions as the other source/drain section, and the first transistor TR.sub.1 (TR.sub.rst) is provided adjacent to the photoelectric conversion section.

A pixel cell includes a nitrogen-implanted region at a semiconductor material-gate oxide proximate interface located in a region above a photodiode. The pixel cell is further devoid of implanted nitrogen in channel regions of a plurality of pixel transistors. Thus, Si—N bonds are formed at the semiconductor material-gate oxide interface in the region above the photodiode, while the channel regions are protected from nitrogen implantation at the semiconductor material-gate oxide interface. Methods of forming the pixel cell are also described.

The present disclosure provides an imaging portion for a time-of-flight device, which has: at least one photo-detection element; at least one overflow gate for the at least one photo-detection element; at least one transfer gate configured to receive at least one transfer signal; at least one transfer gate switch configured to couple or to decouple the at least one overflow gate and the at least one transfer gate in response to at least one transfer gate switch signal.