Abstract: An image sensor including a semiconductor layer. A light absorber layer couples with the semiconductor layer at a pixel of the image sensor and absorbs incident light to substantially prevent the incident light from entering the semiconductor layer. The light absorber layer heats a depletion region of the semiconductor layer in response to absorbing the incident light, creating electron/hole pairs. The light absorber layer may include one or more narrow bandgap materials.

Abstract: An image sensor including a semiconductor layer. A light absorber layer couples with the semiconductor layer at a pixel of the image sensor and absorbs incident light to substantially prevent the incident light from entering the semiconductor layer. The light absorber layer heats a depletion region of the semiconductor layer in response to absorbing the incident light, creating electron/hole pairs. The light absorber layer may include one or more narrow bandgap materials.

Abstract: An image sensor may include a pixel array with global shutter phase detection pixels. The global shutter phase detection pixels may include global shutter charge storage regions. To prevent the global shutter charge storage regions from being exposed to incident light, a shielding layer may be provided. The shielding layer may also cover portions of underlying photodiodes to produce an asymmetric response to incident light in the underlying photodiodes. The shielding layer may be formed as backside trench isolation with an absorptive metal. The absorptive metal may absorb incident light, reducing the likelihood of the incident light reaching the charge storage regions. An additional absorptive layer may also be provided on or in the shielding layer.

Abstract: An image sensor with an array of image sensor pixels is provided. Each image pixel may include a photodiode and associated pixel circuits formed in the front surface of a semiconductor substrate. Buried light shielding structures may be formed on the back surface of the substrate to prevent pixel circuitry that is formed in the substrate between two adjacent photodiodes from being exposed to incoming light. The buried light shielding structures may be lined with absorptive antireflective coating material to prevent light from being reflected off the surface of the buried light shielding structures. Forming buried light shielding structures with absorptive antireflective coating material can help reduce optical pixel crosstalk and enhance signal to noise ratio.

Abstract: Visual and near infrared pixels may have deep photodiodes to ensure sufficient capture of light. The pixels may have a silicon layer that is etched to form a microlens for the pixel. The pixels may include an inversion layer formed over the silicon layer to prevent dark current. Additionally, the pixels may include a conductive layer formed over the inversion layer that further prevents dark current. The conductive layer may be coupled to a bias voltage supply line. The conductive layer may be biased during image acquisition to prevent dark current. During readout, the bias voltage may be pulsed at a lower voltage to ensure all of the collected charge is transferred out of the photodiode during charge transfer.

Abstract: A backside illumination image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode, a storage diode, and associated circuitry formed in a front side of a semiconductor substrate. In accordance with an embodiment, a trench isolation structure may be formed directly over the storage diode but not over the photodiode from a back side of the substrate. The backside trench isolation structure may be filled with absorptive material and can optionally be biased to a ground or negative voltage level. A light shielding layer may also be formed over the backside trench isolation structure on the back side of the substrate. The light shielding layer may be formed from absorptive material or reflective material, and may also be biased to a ground or negative voltage level.

Abstract: Visual and near infrared pixels may have deep photodiodes to ensure sufficient capture of light. The pixels may have a silicon layer that is etched to form a microlens for the pixel. The pixels may include an inversion layer formed over the silicon layer to prevent dark current. Additionally, the pixels may include a conductive layer formed over the inversion layer that further prevents dark current. The conductive layer may be coupled to a bias voltage supply line. The conductive layer may be biased during image acquisition to prevent dark current. During readout, the bias voltage may be pulsed at a lower voltage to ensure all of the collected charge is transferred out of the photodiode during charge transfer.

Abstract: An image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode, a storage diode, and associated circuitry formed in a semiconductor substrate. Buried light shields may be formed on the substrate to prevent regions between two adjacent photodiodes from being exposed to incoming light. In one embodiment, a shallow trench isolation (STI) structure may be formed between the photodiode and the storage diode, and a conductive layer formed from optically absorptive material may be constructed at the bottom of the STI structure. A via may be formed through the STI structure to help bias the conductive layer using a ground or negative voltage. In another embodiment, an isolation ring structure may be formed at the base of the buried light shields. The isolation ring structure may be formed from optically absorptive material and can optionally be biased using a ground or negative voltage.

Abstract: In one form, a touch screen includes an optically transmissive medium, first and second light sources, a detection circuit, and a control circuit. The first light source is positioned to emit light across the optically transmissive medium in a first direction, and the second light source is positioned to emit light across the optically transmissive medium in a second direction orthogonal to the first direction. The detection circuit detects standing wave patterns of light emitted by the first and second light sources along the first and second directions. The control circuit is coupled to the detection circuit and measures a first standing wave pattern in an untouched condition, and a second standing wave pattern in a touched condition. The control circuit detects a touch location in response to a difference between the first standing wave pattern and the second standing wave pattern.

Abstract: A front-side illuminated image sensor with an array of image sensor pixels is provided. Each image pixel may include a photodiode, transistor gate structures, shallow trench isolation structures, and other associated pixel circuits formed in a semiconductor substrate. Buried light shielding structures that are opaque to light may be formed over regions of the substrate to prevent the transistor gate structures, shallow trench isolation structures, and the other associated pixel circuits from being exposed to stray light. Buried light shielding structures formed in this way can help reduce optical pixel crosstalk.

Abstract: A backside illumination image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode, a storage diode, and associated circuitry formed in a front side of a semiconductor substrate. In accordance with an embodiment, a trench isolation structure may be formed directly over the storage diode but not over the photodiode from a back side of the substrate. The backside trench isolation structure may be filled with absorptive material and can optionally be biased to a ground or negative voltage level. A light shielding layer may also be formed over the backside trench isolation structure on the back side of the substrate. The light shielding layer may be formed from absorptive material or reflective material, and may also be biased to a ground or negative voltage level.

Abstract: An image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode, a storage diode, and associated circuitry formed in a semiconductor substrate. Buried light shields may be formed on the substrate to prevent regions between two adjacent photodiodes from being exposed to incoming light. In one embodiment, a shallow trench isolation (STI) structure may be formed between the photodiode and the storage diode, and a conductive layer formed from optically absorptive material may be constructed at the bottom of the STI structure. A via may be formed through the STI structure to help bias the conductive layer using a ground or negative voltage. In another embodiment, an isolation ring structure may be formed at the base of the buried light shields. The isolation ring structure may be formed from optically absorptive material and can optionally be biased using a ground or negative voltage.

Abstract: An image sensor including a semiconductor layer. A light absorber layer couples with the semiconductor layer at a pixel of the image sensor and absorbs incident light to substantially prevent the incident light from entering the semiconductor layer. The light absorber layer heats a depletion region of the semiconductor layer in response to absorbing the incident light, creating electron/hole pairs. The light absorber layer may include one or more narrow bandgap materials.

Abstract: A front-side illuminated image sensor with an array of image sensor pixels is provided. Each image pixel may include a photodiode, transistor gate structures, shallow trench isolation structures, and other associated pixel circuits formed in a semiconductor substrate. Buried light shielding structures that are opaque to light may be formed over regions of the substrate to prevent the transistor gate structures, shallow trench isolation structures, and the other associated pixel circuits from being exposed to stray light. Buried light shielding structures formed in this way can help reduce optical pixel crosstalk.

Abstract: An image sensor including a semiconductor layer. A light absorber layer couples with the semiconductor layer at a pixel of the image sensor and absorbs incident light to substantially prevent the incident light from entering the semiconductor layer. The light absorber layer heats a depletion region of the semiconductor layer in response to absorbing the incident light, creating electron/hole pairs. The light absorber layer may include one or more narrow bandgap materials.

Abstract: An imaging device may include an image sensor having an array of image pixels. The array of image pixels may include one or more infrared pixels that are configured to detect infrared light. The infrared pixels may include reflective structures for increasing quantum efficiency in the infrared spectral range. The reflective structures may include first and second parallel structures formed on opposing sides of a photodiode in an infrared pixel. The reflective structures may be partially transparent to infrared light and non-transparent to visible light. The reflective structures may form an optical cavity so that infrared light that enters an infrared pixel is reflected back and forth between the reflective structures until it is absorbed by the photodiode in the infrared pixel. Reflective structures may also be formed between infrared filters and color filters to suppress optical crosstalk between infrared pixels and color pixels.

Abstract: An image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode and associated pixel circuits formed in a semiconductor substrate. Buried light shields may be formed on the substrate to present pixel circuitry that is formed in the substrate between two adjacent photodiodes from being exposed to incoming light. Metal interconnect muting structures may be formed over the buried light shields. In one embodiment, light blocking structures may be formed to completely seal the interconnect routing structures. The light blocking structures may be formed on top of the buried light shields or on the surface of the substrate. In another embodiment, planar light blocking structures that are parallel to the surface of the substrate may be formed between metal routing layers to help absorb stray light. Light blocking structures formed in these ways can help reduce optical crosstalk and enhance global shutter efficiency.

Abstract: Optical isolation is provided for optically black pixels in image sensors. Image sensors, such as backside illumination (BSI) image sensors, may have an active pixel array and an array having optically black pixels. Isolation structures such as a metal wall may be formed in a dielectric stack between an active pixel array and optically black pixels. Patterned shallow trench isolation regions or polysilicon regions may be formed in a substrate between an active pixel array and optically black pixels. An absorption region such as a germanium-doped absorption region may be formed in a substrate between an active pixel array and optically black pixels. Optical isolation and absorption regions may be formed in a ring surrounding an active pixel array.

Abstract: Resonance enhanced color filter arrays are provided for image sensors. Resonance cavities formed with color filter materials that enhance the color filtering capabilities of the color filter materials. Resonance enhanced color filter arrays may be provided for back side illumination image sensors and front side illumination image sensors. A layer of high refractive index material or metamaterial may be provided between a microlens and a color filter material to serve as a first partially reflecting interface for the resonance cavity. An optional layer of high refractive index material or metamaterial may be provided between color filter material and a substrate. In front side illumination image sensors, color filter material may be provided in a light guide structure that extends through interlayer dielectric. The color filter material in the light guide structure may form at least part of a resonance cavity for a resonance enhanced color filter array.

Abstract: An imaging device may include an image sensor having an array of image pixels. The array of image pixels may include one or more infrared pixels that are configured to detect infrared light. The infrared pixels may include reflective structures for increasing quantum efficiency in the infrared spectral range. The reflective structures may include first and second parallel structures formed on opposing sides of a photodiode in an infrared pixel. The reflective structures may be partially transparent to infrared light and non-transparent to visible light. The reflective structures may form an optical cavity so that infrared light that enters an infrared pixel is reflected back and forth between the reflective structures until it is absorbed by the photodiode in the infrared pixel. Reflective structures may also be formed between infrared filters and color filters to suppress optical crosstalk between infrared pixels and color pixels.