Omnivision Technologies, Inc.

Hidetoshi Nozaki

Howard E Rhodes

Sohei Manabe

Hsin-Chih Tai

Tiejun Dai

Fei Wu

Duli Mao

Yin Qian

Vincent Venezia

Satyadev Hulikal Nagaraja

Ashish A Shah

William Qian

Sasidhar Saladi

Nagaraja Satyadev

Hsin-Chih (Dyson) Tai

Howard M Rhodes

Ashish Shah

An image sensor pixel includes a semiconductor layer, a photosensitive region to accumulate photo-generated charge, a floating node, a trench, and an entrenched transfer gate. The photosensitive region and the trench are disposed within the semiconductor layer. The trench extends into the semiconductor layer between the photosensitive region and the floating node and the entrenched transfer gate is disposed within the trench to control transfer of the photo-generated charge from the photosensitive region to the floating node.

Entrenched transfer gate

Photodetector arrays, image sensors, and other apparatus are disclosed. In one aspect, an apparatus may include a surface to receive light, a plurality of photosensitive regions disposed within a substrate, and a material coupled between the surface and the plurality of photosensitive regions. The material may receive the light. At least some of the light may free electrons in the material. The apparatus may also include a plurality of discrete electron repulsive elements. The discrete electron repulsive elements may be coupled between the surface and the material. Each of the discrete electron repulsive elements may correspond to a different photosensitive region. Each of the discrete electron repulsive elements may repel electrons in the material toward a corresponding photosensitive region. Other apparatus are also disclosed, as are methods of use, methods of fabrication, and systems incorporating such apparatus.

Photodetector array having array of discrete electron repulsive elements

An image sensor having an array of pixels disposed in a substrate. The array of pixels includes photosensitive elements, a color filters, and waveguide walls. The waveguide walls are disposed in the color filters and surround portions of the color filters to form waveguides through the color filters. In some embodiments, metal walls may be coupled to the waveguide walls.

Image sensor having waveguides formed in color filters

An image sensor in accordance with embodiments disclosed herein includes an array of imaging pixels, an insulator layer, and a plurality of metal reflectors. The array of imaging pixels are disposed within a semiconductor layer, where each imaging pixel in the array of imaging pixels includes a photosensitive element configured to receive light from a backside of the image sensor. The insulator layer is disposed on a frontside of the semiconductor layer and the plurality of metal reflectors are disposed within the insulator layer to reflect the light to a respective photosensitive element. A width of each of the plurality of metal reflectors is equal to a width of a metal reflector at the center of the array multiplied by a scaling factor, where the scaling factor is dependent on a distance of the metal reflector from the center of the array.

Image sensor having array of pixels and metal reflectors with widths scaled based on distance from center of the array

An array of pixels is formed using a substrate, where each pixel has a substrate having a backside and a frontside that includes metalization layers, a photodiode formed in the substrate, frontside P-wells formed using frontside processing that are adjacent to the photosensitive region, and an N-type region formed in the substrate below the photodiode. The N-type region is formed in a region of the substrate below the photodiode and is formed at least in part in a region of the substrate that is deeper than the depth of the frontside P-wells.

Image sensor with low electrical cross-talk

An image sensor having an array of pixels disposed in a substrate. Each pixel includes a photosensitive element, a color filter, and waveguide walls. The waveguide walls are disposed in the color filter and surround portions of the color filter to form waveguides through the color filter. The refractive index of the waveguide walls is less than the refractive index of the color filter. The image sensor may be back side illuminated (BSI) or front side illuminated (FSI). In some embodiments, metal walls may be coupled to the waveguide walls.

An image sensor includes a photosensitive region formed in a substrate of an integrated circuit. The substrate has a first layer of metal formed over the surface of the substrate so the first layer of metal defines a first aperture that has a first aperture width through with the incident light passes before illuminating the photosensitive region. The first aperture width is equal to or less than the width of the photosensitive region below the first aperture. The substrate also has a second layer of metal formed over the first layer of metal. The second aperture has a second aperture width that is wider than the first aperture width. The first and second apertures focus the incident light onto the photosensitive region.

Image sensor with focusing interconnections

An image sensor includes a semiconductor layer that filters light of different wavelengths. For example, the semiconductor layer absorbs photons of shorter wavelengths and passes more photons of longer wavelengths such that the longer wavelength photons often pass through without being absorbed. An imaging pixel having a photodiode is formed near a front side of the semiconductor layer. A dopant layer is formed below the photodiode near a back side of the semiconductor layer. A mirror that primarily reflects photons of longer visible wavelengths is disposed on the back side of the semiconductor layer.

Image sensor with backside passivation and metal layer

A method of operation of a backside illuminated (BSI) pixel array includes acquiring an image signal with a first photosensitive region of a first pixel within the BSI pixel array. The image signal is generated in response to light incident upon a backside of the first pixel. The image signal acquired by the first photosensitive region is transferred to pixel circuitry of the first pixel disposed on a frontside of the first pixel opposite the backside. The pixel circuitry at least partially overlaps the first photosensitive region of the first pixel and extends over die real estate above a second photosensitive region of a second pixel adjacent to the first pixel such that the second pixel donates die real estate unused by the second pixel to the first pixel to accommodate larger pixel circuitry than would fit within the first pixel.

Circuit and photo sensor overlap for backside illumination image sensor

A backside illuminated ('BSI') imaging sensor pixel includes a photodiode region and pixel circuitry. The photodiode region is disposed within a semiconductor die for accumulating an image charge in response to light incident upon a backside of the BSI imaging sensor pixel. The pixel circuitry includes transistor pixel circuitry disposed within the semiconductor die between a frontside of the semiconductor die and the photodiode region. At least a portion of the pixel circuitry overlaps the photodiode region.

An image sensor includes a semiconductor layer that low-pass filters light of different wavelengths. For example, the semiconductor layer proportionately absorbs photons of shorter wavelengths and proportionately passes more photons of longer wavelengths such that the longer wavelength photons often pass through without being absorbed. An imaging pixel having a photodiode is formed on a front surface of the semiconductor layer, where the photodiode is an Nregion formed within the P-type region of the semiconductor layer. A Player is formed between the Nregion of the photodiode and a back surface of the semiconductor layer. A mirror that primarily reflects photons of red and/or infra-red wavelengths is formed on the back surface of the semiconductor layer.

An array of pixels is formed using a substrate, where each pixel has a substrate having an incident side for receiving incident light, a photosensitive region formed in the substrate, and a reflector having a complex-shaped surface. The reflector is formed in a portion of the substrate that is opposed to the incident side such that light incident on the complex-shaped surface of the reflector is reflected towards the photosensitive region.

Frontside illuminated image sensor comprising a complex-shaped reflector

An image sensor pixel includes a substrate, an epitaxial layer, and a light collection region. The substrate is doped to have a first conductivity type. The epitaxial layer is disposed over the substrate and doped to have a second conductivity type opposite of the first conductivity type. The light collection region is disposed within the epitaxial layer for collecting photo-generated charge carriers. The light collection region is doped to have the first conductivity type as well.

Growing community of inventors

Sunnyvale, CA, United States of America

Hidetoshi Nozaki