A depth sensor includes a first pixel including a plurality of first photo transistors each receiving a first photo gate signal, a second pixel including a plurality of second photo transistors each receiving a second photo gate signal, a third pixel including a plurality of third photo transistors each receiving a third photo gate signal, a fourth pixel including a plurality of fourth photo transistors each receiving a fourth photo gate signal, and a photoelectric conversion element shared by first to fourth photo transistors of the plurality of first to fourth photo transistors.

Photosensors may be formed on a front side of a semiconductor substrate. An optical refraction layer having a first refractive index may be formed on a backside of the semiconductor substrate. A grid structure including openings is formed over the optical refraction layer. A masking material layer is formed over the grid structure and the optical refraction layer. The masking material layer may be anisotropically etched using an anisotropic etch process that collaterally etches a material of the optical refraction layer and forms non-planar distal surface portions including random protrusions on physically exposed portions of the optical refraction layer. An optically transparent layer having a second refractive index that is different from the first refractive index may be formed on the non-planar distal surface portions of the optical refraction layer. A refractive interface refracts incident light in random directions, and improves quantum efficiency of the photosensors.

A method for manufacturing a back-illuminated solid-state imaging device includes a first step of preparing a first conduction-type semiconductor layer having a front surface and a back surface, a second step of forming a first asperity region on the front surface of the semiconductor layer by selectively etching the front surface of the semiconductor layer, a third step of forming a second asperity region on the front surface of the semiconductor layer by smoothening asperities of the first asperity region, and a fourth step of forming an insulating layer along the second asperity region and forming a plurality of charge transfer electrodes on the insulating layer.

An image sensing device includes a pixel array configured to include a plurality of pixel groups arranged in a matrix structure. Each of the pixel groups includes an optical filter configured to selectively pass incident light, a plurality of photoelectric conversion regions disposed below the optical filter and arranged in a matrix structure, a first isolation structure disposed between the photoelectric conversion regions and other pixel groups, a plurality of second isolation structures disposed between two adjacent photoelectric conversion regions from among the photoelectric conversion regions, and a third isolation structure disposed between the second isolation structures, and configured to interconnect the second isolation structures. The third isolation structure includes a cavity region formed adjacent to contact any one of the photoelectric conversion regions.

Disclosed is a SPAD pixel for a backside illuminated image sensor. More particularly, the SPAD pixel may improve sensitivity to long wavelengths by maximizing the depth of a PN junction in an epitaxial layer in the SPAD substrate.

An image sensor includes a substrate having a plurality of pixel regions and a deep device isolation pattern disposed in the substrate between the pixel regions. The pixel regions include first, second, third, and fourth pixel regions, which are adjacent to each other in first and second directions. The deep device isolation pattern includes first portions interposed between the first and second pixel regions and between the third and fourth pixel regions and spaced apart from each other in the second direction, and second portions interposed between the first and third pixel regions and between the second and fourth pixel regions and spaced apart from each other in the first direction. The first pixel region includes a first extended active pattern, which is extended to the second pixel region in the first direction and is disposed between the first portions of the deep device isolation pattern.

Provided is an image sensor including a color separating lens array and an electronic device including the color sensor. The image sensor includes a sensor substrate including a plurality of first pixels and a plurality of second pixels and having a two-dimensional array of unit pixels including the first pixel and the second pixel; and a color separating lens array configured to concentrate light of a first wavelength on each of the first pixels, and concentrate light of a second wavelength on each of the second pixels, wherein at least one pixel of the unit pixel includes a plurality of light sensing cells for independently sensing light by being electrically separated by a deep trench isolation (DTI) structure, and the color separating lens array includes a nanopost array, which does not include a nanopost provided on the DTI structure.

Provided is an image sensor including: a substrate including a first pixel domain and a second pixel domain that are adjacent to each other in a first direction, the first pixel domain including first pixels and the second pixel domain including second pixels; a first color filter provided on a first surface of the substrate and vertically overlapping the first pixels; a first microlens provided on the first color filter and each of the first pixels; and a second microlens provided on the first surface of the substrate and vertically overlapping at least a portion of each of the second pixels, wherein a second refractive index of the second microlens is greater than a first refractive index of the first microlens, and wherein a level difference between an uppermost part of the first microlens and an uppermost part of the second microlens is within about 2% of a maximum height of the first microlens.

A method of fabricating an image sensor includes forming a semiconductor substrate of a first conductivity type, forming a pixel isolation trench in in the semiconductor substrate to define pixel regions, forming a liner insulating layer in the pixel isolation trench, doping the liner insulating layer with dopants of a first conductivity type, forming a semiconductor layer on the liner insulating layer to fill the pixel isolation trench after the doping of the dopants, and performing a thermal treatment process on the semiconductor substrate.

The incidence of incident light transmitted through a photoelectric conversion unit onto a charge holding unit, a pixel in the adjacency, and the like can be blocked in a pixel. An image sensor includes a pixel, a wiring layer, and an incident light attenuation unit. The pixel includes a photoelectric conversion unit that is formed in a semiconductor substrate and performs photoelectric conversion based on incident light, and a pixel circuit that generates an image signal according to a charge generated by the photoelectric conversion. The wiring layer is arranged on a surface of the semiconductor substrate different from a surface onto which the incident light is incident, and transports either the image signal or a signal applied to the pixel circuit. The incident light attenuation unit attenuates the incident light transmitted through the photoelectric conversion unit.