Abstract: Embodiments of the present invention are directed to an image sensor having pixel transistors and peripheral transistors disposed in a silicon substrate. For some embodiments, a protective coating is disposed on the peripheral transistors and doped silicon is epitaxially grown on the substrate to form lightly-doped drain (LDD) areas for the pixel transistors. The protective oxide may be used to prevent epitaxial growth of silicon on the peripheral transistors during formation of the LDD areas of the pixel transistors.

Abstract: A backside illuminated imaging pixel with improved angular response includes a semiconductor layer having a front and a back surface. The imaging pixel also includes a photodiode region formed in the semiconductor layer. The photodiode region includes a first and a second n-region. The first n-region has a centerline projecting between the front and back surfaces of the semiconductor layer. The second n-region is disposed between the first n-region and the back surface of the semiconductor layer such that the second n-region is offset from the centerline of the first n-region.

Abstract: An array of pixels is formed using a substrate. Each pixel can be formed on the substrate, which has a backside and a frontside that includes metalization layers. A photodiode is formed in the substrate and frontside P-wells are formed using frontside processing that are adjacent to the photosensitive region. A first N-type region is formed in the substrate below the photodiode. A second N-type region is formed in a region of the substrate below the first N-type region and is formed using backside processing.

Abstract: A color pixel array includes first, second, and third pluralities of color pixels each including a photosensitive region disposed within a first semiconductor layer. In one embodiment, a second semiconductor layer including deep dopant regions is disposed below the first semiconductor layer. The deep dopant regions each reside below a corresponding one of the first plurality of color pixels but substantially not below the second and third pluralities of color pixels. In one embodiment, buried wells are disposed beneath the second and third pluralities of color pixels but substantially not below the first plurality of color pixels.

Abstract: An image sensor includes an optical sensor region, a stack of dielectric and metal layers, and an embedded layer. The optical sensor is disposed within a semiconductor substrate. The stack of dielectric and metal layers are disposed on the front side of the semiconductor substrate above the optical sensor region. The embedded focusing layer is disposed on the backside of the semiconductor substrate in a Backside Illuminated (BSI) image sensor, supported by a support grid, or a support grid composed of the semiconductor substrate.

Abstract: The disclosure describes embodiments of a process comprising forming a pixel on a frontside of a substrate, the substrate having a frontside, a backside, and a thickness substantially equal to a distance between the frontside and the backside. The thickness of the substrate is reduced by removing material from the backside of the substrate to allow for backside illumination of the pixel, and the backside of the substrate is treated with a hydrogen plasma to passivate the backside. The disclosure also describes embodiments of an apparatus comprising a semiconductor wafer having a frontside, a backside, and a thickness substantially equal to a distance between the frontside and the backside, and a pixel formed on the frontside, wherein the thickness of the wafer is selected and adjusted to allow for illumination of the pixel through the backside of the wafer, and wherein the backside is treated with a hydrogen plasma to passivate the backside.

Abstract: An image sensor includes a substrate having a surface at which incident light is received. A pixel array is formed over and within the substrate. The pixel array includes a first and a second pixel arranged to receive light of different colors. The first pixel includes a photosensitive region formed in the substrate and has a first anti-reflective coating (ARC) layer formed over the photosensitive region. The first ARC layer has a first thickness that produces destructive interference above the first ARC layer in response to the incident light. The second pixel includes a photosensitive region formed in the substrate, and a second ARC layer formed over the photosensitive region that produces destructive interference above the second ARC layer in response to the incident light.

Abstract: An image sensor with a high full-well capacity includes a photosensitive region, a transfer gate, and sidewall spacers. The photosensitive region is formed to accumulate an image charge in response to light. The transfer gate disposed adjacent to the photosensitive region and coupled to selectively transfer the image charge from the photosensitive region to other pixel circuitry. First and second sidewall spacers are disposed on either side of the transfer gate. The first sidewall spacer closest to the photosensitive region is narrower than the second sidewall spacer. In some cases, the first sidewall spacer may be omitted.

Abstract: 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.

Abstract: An image sensor includes an optical sensor region, a stack of dielectric and metal layers, and a buried focusing layer. The optical sensor is disposed within a semiconductor substrate. The stack of dielectric and metal layers are disposed on the semiconductor substrate above the optical sensor region. The metal layers include optical pass-throughs aligned to expose an optical path through the stack form a top dielectric layer through to the optical sensor region. The buried focusing layer is disposed over a conforming metal layer of the metal layers within the stack. The buried focusing layer includes a curved surface conformed by the optical pass-through of the conforming metal layer to focus light onto the optical sensor region.

Abstract: An image sensor includes an optical sensor region, a stack of dielectric and metal layers, and a buried focusing layer. The optical sensor is disposed within a semiconductor substrate. The stack of dielectric and metal layers are disposed on the semiconductor substrate above the optical sensor region. The metal layers include optical pass-throughs aligned to expose an optical path through the stack form a top dielectric layer through to the optical sensor region. The buried focusing layer is disposed over a conforming metal layer of the metal layers within the stack. The buried focusing layer includes a curved surface conformed by the optical pass-through of the conforming metal layer to focus light onto the optical sensor region.

Abstract: A backside illuminated imaging sensor includes a vertical stacked sensor that reduces cross talk by using different silicon layers to form photodiodes at separate levels within a stack (or separate stacks) to detect different colors. Blue light-, green light-, and red light-detection silicon layers are formed, with the blue light detection layer positioned closest to the backside of the sensor and the red light detection layer positioned farthest from the backside of the sensor. An anti-reflective coating (ARC) layer can be inserted in between the red and green light detection layers to reduce the optical cross talk captured by the red light detection layer. Amorphous polysilicon can be used to form the red light detection layer to boost the efficiency of detecting red light.

Abstract: An image sensor having a plurality of micro-lenses disposed on a semiconductor substrate. A first micro-lens has a different focal length, height, shape, curvature, thickness, etc., than a second micro-lens. The image sensor may be back side illuminated or front side illuminated.

Abstract: 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.

Abstract: A backside illuminated imaging sensor includes a semiconductor having an imaging pixel that can include a photodiode region, an insulation layer, and a reflective layer. The photodiode is typically formed in the frontside of the semiconductor substrate. A surface shield layer can be formed on the frontside of the photodiode region. A light reflecting layer can be formed using silicided polysilicon on the frontside of the sensor. The photodiode region receives light from the back surface of the semiconductor substrate. When a portion of the received light propagates through the photodiode region to the light reflecting layer, the light reflecting layer reflects the portion of light received from the photodiode region towards the photodiode region. The silicided polysilicon light reflecting layer also forms a gate of a transistor for establishing a conductive channel between the photodiode region and a floating drain.

Abstract: An array of pixels is formed using a substrate having a frontside and a backside that is for receiving incident light. Each pixel typically includes metallization layers included in the frontside of the substrate, a photosensitive region formed in the backside of the substrate, and a trench formed around the photosensitive region in the backside of the substrate. The trench causes the incident light to be directed away from the trench and towards the photosensitive region.

Abstract: 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.

Abstract: A backside illuminated imaging sensor includes a semiconductor layer and an infrared detecting layer. The semiconductor layer has a front surface and a back surface. An imaging pixel includes a photodiode region formed within the semiconductor layer. The infrared detecting layer is disposed above the front surface of the semiconductor layer to receive infrared light that propagates through the imaging sensor from the back surface of the semiconductor layer.

Abstract: A backside illuminated imaging sensor includes a semiconductor layer, a metal interconnect layer and a silicide light reflecting layer. The semiconductor layer has a front surface and a back surface. An imaging pixel that includes a photodiode region is formed within the semiconductor layer. The metal interconnect layer is electrically coupled to the photodiode region and the silicide light reflecting layer is coupled between the metal interconnect layer and the front surface of the semiconductor layer. In operation, the photodiode region receives light from the back surface of the semiconductor layer, where a portion of the received light propagates through the photodiode region to the silicide light reflecting layer. The silicide light reflecting layer is configured to reflect the portion of light received from the photodiode region.

Abstract: An imaging sensor pixel array includes a semiconductor substrate, a plurality of active pixels and at least one black reference pixel. The plurality of active pixels are disposed in the semiconductor substrate for capturing an image. Each of the active pixels includes a first region for receiving light including a p-n junction for accumulating an image charge and active pixel circuitry coupled to the first region to readout the image charge. The black reference pixel is also disposed within the semiconductor substrate for generating a black level reference value. The black reference pixel includes a second region for receiving light without a p-n junction and black pixel circuitry coupled to the photodiode region without the p-n junction to readout a black level reference signal.