Abstract: An image sensor may include high dynamic range imaging pixels having an inner sub-pixel surrounded by an outer sub-pixel. To steer light away from the inner sub-pixel and towards the outer sub-pixel, the high dynamic range imaging pixels may be covered by a toroidal microlens. To mitigate cross-talk caused by high-angled incident light, various microlens arrangements may be used. A toroidal microlens may have planar portions on its outer perimeter. A toroidal microlens may be covered by four additional microlenses, each additional microlens positioned in a respective corner of the pixel. Each pixel may be covered by four microlenses in a 2×2 arrangement, with an opening formed by the space between the four microlenses overlapping the inner sub-pixel.

Abstract: An image sensor may include pixels having nested sub-pixels. A pixel with nested sub-pixels may include an inner sub-pixel that has either an elliptical or a rectangular light collecting area. The inner sub-pixel may be formed in a substrate and may be immediately surrounded by a sub-pixel group that includes one or more sub-pixels. The inner sub-pixel may have a light collecting area at a surface that is less sensitive than the light collecting area of the one or more outer sub-pixel groups. Microlenses may be formed over the nested sub-pixels, to direct light away from the inner sub-pixel group to the outer sub-pixel groups in nested sub-pixels. A color filter of a single color may be formed over the nested sub-pixels. Hybrid color filters having a single color filter region over the inner sub-pixel and a portion of the one or more outer sub-pixel groups may also be used.

Abstract: An image sensor may include an array of pixels. Pixels in the array may include a photodiode that converts incident light into electrical charge and a charge storage region for storing the electrical charge before it is read out from the pixel. Pixels in the array may include a microlens formed over the photodiode that directs light onto the photodiode. Pixels in the array may include an additional array of microlenses between the microlens and the photodiode. The additional array of microlenses may direct light away from the charge storage region to prevent charge stored at the charge storage region from being affected by light that is not incident upon the photodiode. The image sensor may be a backside illuminated image sensor that operates in a global shutter mode.

Abstract: Color filters may affect imaging performance attributes such as low light sensitivity, color accuracy, and modulation transfer function (MTF). In an image pixel array, these factors are influenced by both the spectral absorption and pattern of the color filter elements. Different portions of an image sensor may prioritize different imaging performance attributes. Accordingly, in certain applications it may be beneficial for color filter characteristics to vary across an image sensor. Different color filters of the same color may have different structures to optimize imaging performance across the image sensor.

Abstract: An image sensor may include an array of pixels. Pixels in the array may include a photodiode that converts incident light into electrical charge and a charge storage region for storing the electrical charge before it is read out from the pixel. Pixels in the array may include a microlens formed over the photodiode that directs light onto the photodiode. Pixels in the array may include an additional array of microlenses between the microlens and the photodiode. The additional array of microlenses may direct light away from the charge storage region to prevent charge stored at the charge storage region from being affected by light that is not incident upon the photodiode. The image sensor may be a backside illuminated image sensor that operates in a global shutter mode.

Abstract: An imaging system may include an image sensor die, which may be backside illuminated (BSI). A light shielding layer and a conductive layer may be formed in the image sensor die. First and second portions of the conductive layer may be electrically isolated, so that the second conductive portion may be coupled to other power supply signals through a bond pad region, while the light shield may be shorted to ground. Optionally, the first and second portions may both be coupled to ground. The light shield may also be shorted through the bond pad region in a continuous conductive layer. A through oxide via may be formed in the image sensor die to couple metal interconnect structures to the conductive layer. Color filter containment structures may be formed over active image sensor pixels on the image sensor die, which may be selectively etched to improve planarity.

Abstract: Color filters may affect imaging performance attributes such as low light sensitivity, color accuracy, and modulation transfer function (MTF). In an image pixel array, these factors are influenced by both the spectral absorption and pattern of the color filter elements. Different portions of an image sensor may prioritize different imaging performance attributes. Accordingly, in certain applications it may be beneficial for color filter characteristics to vary across an image sensor. Different color filters of the same color may have different structures to optimize imaging performance across the image sensor.

Abstract: Color filters may affect imaging performance attributes such as low light sensitivity, color accuracy, and modulation transfer function (MTF). In an image pixel array, these factors are influenced by both the spectral absorption and pattern of the color filter elements. Different portions of an image sensor may prioritize different imaging performance attributes. Accordingly, in certain applications it may be beneficial for color filter characteristics to vary across an image sensor. Different color filters of the same color may have different structures to optimize imaging performance across the image sensor.

Abstract: A semiconductor wafer has a plurality of non-rectangular semiconductor die with an image sensor region. The non-rectangular semiconductor die has a circular, elliptical, and shape with non-linear side edges form factor. The semiconductor wafer is singulated with plasma etching to separate the non-rectangular semiconductor die. A curved surface is formed in the image sensor region of the non-rectangular semiconductor die. The non-rectangular form factor effectively removes a portion of the base substrate material in a peripheral region of the semiconductor die to reduce stress concentration areas and neutralize buckling in the curved surface of the image sensor region. A plurality of openings or perforations can be formed in a peripheral region of a rectangular or non-rectangular semiconductor die to reduce stress concentration areas and neutralize buckling. A second semiconductor die can be formed in an area of the semiconductor wafer between the non-rectangular semiconductor die.

Abstract: Imaging systems may include fluidic color filter elements to increase the flexibility of the system. An imaging system may include a number of fluid reservoirs with different color filter element fluids. The imaging sensor may include a number of separated color filter chambers. Fluids from the fluid reservoirs may be directed to specific color filter chambers as desired, with the option to change the color filter fluid in a chamber to a different color filer fluid at any time. To move the fluids to and from the fluid reservoirs to the color filter chambers, electrowetting may be used. The color filter chambers may be interposed between a ground electrode and a number of patterned electrodes. Voltages may be applied to the patterned electrodes to move the fluid to desired positions within the chambers.

Abstract: An image sensor may include pixels having nested sub-pixels. A pixel with nested sub-pixels may include an inner sub-pixel that has either an elliptical or a rectangular light collecting area. The inner sub-pixel may be formed in a substrate and may be immediately surrounded by a sub-pixel group that includes one or more sub-pixels. The inner sub-pixel may have a light collecting area at a surface that is less sensitive than the light collecting area of the one or more outer sub-pixel groups. Microlenses may be formed over the nested sub-pixels, to direct light away from the inner sub-pixel group to the outer sub-pixel groups in nested sub-pixels. A color filter of a single color may be formed over the nested sub-pixels. Hybrid color filters having a single color filter region over the inner sub-pixel and a portion of the one or more outer sub-pixel groups may also be used.

Abstract: A semiconductor wafer has a plurality of non-rectangular semiconductor die with an image sensor region. The non-rectangular semiconductor die has a circular, elliptical, and shape with non-linear side edges form factor. The semiconductor wafer is singulated with plasma etching to separate the non-rectangular semiconductor die. A curved surface is formed in the image sensor region of the non-rectangular semiconductor die. The non-rectangular form factor effectively removes a portion of the base substrate material in a peripheral region of the semiconductor die to reduce stress concentration areas and neutralize buckling in the curved surface of the image sensor region. A plurality of openings or perforations can be formed in a peripheral region of a rectangular or non-rectangular semiconductor die to reduce stress concentration areas and neutralize buckling. A second semiconductor die can be formed in an area of the semiconductor wafer between the non-rectangular semiconductor die.

Abstract: An image sensor may have a pixel array, and the pixel array may include a plurality of image pixels that gather image data and a plurality of phase detection pixels that gather phase information. The phase detection pixels may be arranged in phase detection pixel blocks, and each phase detection pixel group may include edge pixels. The edge pixels of each phase detection pixel group may be covered by microlenses that also cover a portion of a center pixel. The pixel array may also include high dynamic range pixel blocks. Each high dynamic range pixel block may include pixels within the phase detection pixel block and other pixels (e.g., corner pixels). A subset of the plurality of image pixels in the pixel array may be arranged in pixel blocks. Each pixel block may include a phase detection pixel block and a high dynamic range pixel block.

Abstract: An imaging system may include several different types of pixels that are each configured to detect different characteristics of light received at the imaging system. An imaging system may include image sensing pixels that detect the wavelength and intensity of the light, direction sensing pixels that detect the directionality of the light, polarization sensing pixels that detect a polarization state of the light, and diffractive wavelength separation pixels that detect multiple different wavelength components of the light. One or more pixels of the different types may be arranged in a pixel cluster. A pixel cluster that includes different pixel types may detect spatially correlated information for multiple characteristics of the light. Multiple pixel clusters may be arranged in a pixel array that generates an image based on spatially correlated information for the different characteristics of the light.

Abstract: Imaging systems may include fluidic color filter elements to increase the flexibility of the system. An imaging system may include a number of fluid reservoirs with different color filter element fluids. The imaging sensor may include a number of separated color filter chambers. Fluids from the fluid reservoirs may be directed to specific color filter chambers as desired, with the option to change the color filter fluid in a chamber to a different color filer fluid at any time. To move the fluids to and from the fluid reservoirs to the color filter chambers, electrowetting may be used. The color filter chambers may be interposed between a ground electrode and a number of patterned electrodes. Voltages may be applied to the patterned electrodes to move the fluid to desired positions within the chambers.

Abstract: An image sensor with an array of pixels is provided. The array may include a semiconductor substrate having opposing first and second sides. A first photodiode region may be implanted in the semiconductor substrate through the first side. A second photodiode region may be implanted in the semiconductor substrate through the second side. The second photodiode region may be implanted to overlap with the first photodiode region in the semiconductor substrate to form a continuous photodiode region that extends from the first side to the second side of the substrate. The continuous region may generate charge in response to image light. The continuous region may belong to a single pixel that generates an image signal from the charge. The image signal may be conveyed to readout circuitry via metallization layers formed over the substrate. The first and second photodiode regions may be thermally activated prior to forming the metallization layers.

Abstract: A semiconductor wafer has a plurality of non-rectangular semiconductor die with an image sensor region. The non-rectangular semiconductor die has a circular, elliptical, and shape with non-linear side edges form factor. The semiconductor wafer is singulated with plasma etching to separate the non-rectangular semiconductor die. A curved surface is formed in the image sensor region of the non-rectangular semiconductor die. The non-rectangular form factor effectively removes a portion of the base substrate material in a peripheral region of the semiconductor die to reduce stress concentration areas and neutralize buckling in the curved surface of the image sensor region. A plurality of openings or perforations can be formed in a peripheral region of a rectangular or non-rectangular semiconductor die to reduce stress concentration areas and neutralize buckling. A second semiconductor die can be formed in an area of the semiconductor wafer between the non-rectangular semiconductor die.

Abstract: An image sensor may include a pixel array with high dynamic range functionality and phase detection pixels. The phase detection pixels may be arranged in phase detection pixel groups. Each phase detection pixel group may include three adjacent pixels arranged consecutively in a line. A single microlens may cover all three pixels in the phase detection pixel group, or two microlenses may combine to cover the three pixels in the phase detection pixel group. The edge pixels in each phase detection pixel group may have the same integration time and the same color. The middle pixel in each phase detection pixel group may have the same or different color as the edge pixels, and the same or different integration time as the edge pixels. Phase detection pixel groups may also be formed from two pixels that each are 1.5 times the size of neighboring pixels.

Abstract: A backside illuminated image sensor with an array of pixels formed in a substrate is provided. To improve surface planarity, bond pads formed at the periphery of the array of pixels may be recessed into a back surface of the substrate. The bond pads may be recessed into a semiconductor layer of the substrate, may be recessed into a window in the semiconductor layer, or may be recessed in a passivation layer and covered with non-conductive material such as resin. In order to further improve surface planarity, a window may be formed in the semiconductor layer at the periphery of the array of pixels, or scribe region, over alignment structures. By providing an image sensor with improved surface planarity, device yield and time-to-market may be improved, and window framing defects and microlens/color filter non-uniformity may be reduced.

Abstract: An image sensor may have a pixel array, and the pixel array may include a plurality of image pixels that gather image data and a plurality of phase detection pixels that gather phase information. The phase detection pixels may be arranged in phase detection pixel blocks, and each phase detection pixel group may include edge pixels. The edge pixels of each phase detection pixel group may be covered by microlenses that also cover a portion of a center pixel. The pixel array may also include high dynamic range pixel blocks. Each high dynamic range pixel block may include pixels within the phase detection pixel block and other pixels (e.g., corner pixels). A subset of the plurality of image pixels in the pixel array may be arranged in pixel blocks. Each pixel block may include a phase detection pixel block and a high dynamic range pixel block.