Patent application number | Description | Published |
20100308427 | IMAGE SENSORS WITH LIGHT GUIDES - An image sensor may be formed from a planar semiconductor substrate. The image sensor may have an array of pixels. Each pixel may have a photosensitive element that is formed in the substrate and may have a light guide in a dielectric stack that guides light from a microlens and color filter to the photosensitive element. The light guides in pixels that are offset from the center of the image sensor may be tilted so that their longitudinal axes each form a non-zero angle with a vertical axis that lies perpendicular to the planar semiconductor substrate. These light guides may have laterally elongated openings that help collect light. A light guide may have a lower opening that matches the size of an associated photosensitive element. Photosensitive elements that are laterally offset from the center of the image sensor may be tilted. Pixels of different colors may have off-center photosensitive elements. | 12-09-2010 |
20110032398 | IMAGE SENSOR WITH MULTILAYER INTERFERENCE FILTERS - Image sensors are provided for electronic imaging devices. An image sensor can be formed from an array of image pixels. Bragg-type multilayer interference filters can be formed for the image sensor using dielectric layers with alternating high and low indices of refraction. The multilayer interference filters can be configured to form band-pass filters of desired colors and infrared-blocking filters. Dielectric layers with non-flat bulk absorption properties may be used to tune the absorption of the filters. The interference filters may be provided in a uniform pattern so that an image sensor exhibits a monochrome response or may be arranged in a multicolor color filter array pattern such as a Bayer pattern. | 02-10-2011 |
20110241145 | BACKSIDE ILLUMINATION IMAGE SENSORS WITH REFLECTIVE LIGHT GUIDES - Image sensors with backside illumination image pixel arrays are provided. An image pixel array may have image pixels that are formed on a silicon substrate having front and back surfaces. The pixel array may have photodiodes formed in the front surface. A dielectric stack may be formed on the front surface. The dielectric stack may include interconnect structures and reflective light guides. A color filter array may be formed on the back surface of the substrate. Microlenses may be formed on the color filter array from the side facing the back surface. The pixel array may receive incoming light through the microlenses. The incoming light may enter the substrate through the back surface. The incoming light may penetrate the substrate and may be reflected by a light reflector in the reflective light guide back towards the photodiode. The image pixel array may exhibit improved quantum efficiency, sensitivity, and image contrast. | 10-06-2011 |
20120188419 | Multisection Light Guides for Image Sensor Pixels - Image sensors may contain arrays of image sensor pixels, each of which includes a microlens and a photosensitive element. A multisection light guide that is made up of multiple light guide layers may be interposed between the microlens and the photosensitive element. The light guide layers may have alternating indicies of refraction to form a spectral filter. The lateral dimensions of the light guide layers may also be configured so that the light guide layers perform spectral filtering. Light guide shapes and sizes may be altered as a function of the lateral position of each image sensor pixel within the image sensor array. The uppermost light guide may be aligned with the microlens and the lowermost light guide may be aligned with the photosensitive element. The lateral positions of each light guide may be laterally shifted with respect to the next to form a staggered stack of light guides. | 07-26-2012 |
20120273652 | SYSTEMS AND METHODS FOR IMAGE SENSING - Systems and methods for image sensing are disclosed. An image sensor includes a pixel having an active region and a plurality of reflective interfaces. The active region is configured to convert light absorbed by the pixel into an electrical signal. The plurality of reflective interfaces cause the light absorbed by the pixel to resonate within the active region. A method for converting absorbed light into an electrical signal with an image sensor includes absorbing light with the pixel of the image sensor, and reflecting the absorbed light with a plurality of reflective interfaces embedded in the pixel to generate a resonance within the active region. | 11-01-2012 |
20120274568 | COMPLETE DIGITAL HOLOGRAPHIC IMAGE SENSOR-PROJECTOR COMPUTING UNIT - A hologram projecting system includes a coherent light source for emitting a reference beam onto a real object; and an image sensor for receiving the reference beam and a scattered beam reflected from the real object, and recording a Fourier image of the real object. Also included is a modulator for receiving the Fourier image. The reference beam is passed through the modulator, and configured to interact with the Fourier image to form a virtual image of the real object. The image sensor includes an n×m pixel array, where n and m are numbers of rows and columns, respectively. The modulator includes an n×m pixel array corresponding to the n×m pixel array of the image sensor. The pixels in the n×m pixel array of the image sensor control transmissivity of light in corresponding pixels of the n×m pixel array of the modulator. | 11-01-2012 |
20120280273 | METHODS AND SUBSTRATES FOR LASER ANNEALING - Methods and substrates for laser annealing are disclosed. The substrate includes a target region to be annealed and a plurality of reflective interfaces. The reflective interfaces cause energy received by the substrate to resonate within the target region. The method includes emitting energy toward the substrate with a laser, receiving the energy with the substrate, and reflecting the received energy with a plurality of reflective interfaces embedded in the substrate to generate a resonance within the target region. | 11-08-2012 |
20120281099 | DOUBLE PASS BACK SIDE IMAGE SENSOR SYSTEMS AND METHODS - Double pass back side image (BSI) sensor systems and methods are disclosed. The BSI sensor may include a substrate, pixel reflectors formed on the substrate, and pixel photodiodes fabricated in the substrate, each pixel photodiode positioned over a respective one of the pixel reflectors. Micro-lenses may be formed over each photodiode and an image filter may be formed between the photodiodes and the micro-lenses. The pixels reflectors, photodiodes, micro-lenses, and filter may be formed using CMOS fabrication. | 11-08-2012 |
20130113968 | OPTICAL ISOLATION OF OPTICALLY BLACK PIXELS IN IMAGE SENSORS - 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. | 05-09-2013 |
20130119236 | RESONANCE ENHANCED ABSORPTIVE COLOR FILTERS - 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 tor a resonance enhanced color filter array. | 05-16-2013 |
20130134535 | BACKSIDE IMAGE SENSOR PIXEL WITH SILICON MICROLENSES AND METAL REFLECTOR - A backside illumination (BSI) image sensor pixel that includes microlenses with elevated refractive indices is provided. The image sensor pixel may include a photodiode formed in a silicon substrate, a first microlens formed in a back surface of the substrate, a second microlens formed over a front surface of the substrate, a dielectric stack formed on the front surface of the substrate, and a reflective structure formed in the dielectric stack above the second microlens. The first microlens may be fabricated by forming shallow trench isolation structures in the back surface. The second microlens may be fabricated by depositing polysilicon on the front substrate of the substrate. The first microlens may serve to concentrate light towards the photodiode, whereas the second microlens may serve to collimate light that traverses through the substrate so that light exiting the second microlens will reflect off the reflective structure and back into the photodiode. | 05-30-2013 |
20140077061 | BACKSIDE ILLUMINATED IMAGE SENSORS HAVING BURIED LIGHT SHIELDS WITH ABSORPTIVE ANTIREFLECTIVE COATING - 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. | 03-20-2014 |
20140077283 | IMAGE SENSORS HAVING BURIED LIGHT SHIELDS WITH ANTIREFLECTIVE COATING - 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 a semiconductor substrate. Buried light shielding structures may be formed on 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 global shutter efficiency. | 03-20-2014 |
20140078359 | IMAGE SENSOR PIXELS WITH LIGHT GUIDES AND LIGHT SHIELD STRUCTURES - 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. | 03-20-2014 |
20140085517 | BACKSIDE ILLUMINATED IMAGE SENSOR PIXELS WITH DARK FIELD MICROLENSES - A backside illuminated image sensor with an array of image sensor pixels is provided. Each image pixel may include a photodiode and associated pixel circuits formed in a front surface of a semiconductor substrate. Silicon inner microlenses may be formed on a back surface of the semiconductor substrate. In particular, positive inner microlenses may be formed over the photodiodes, whereas negative inner microlenses may be formed over the associated pixel circuits. Buried light shielding structures may be formed over the negative inner microlenses to prevent pixel circuitry that is formed in the substrate between two neighboring 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 antireflective coating material can reduce optical pixel crosstalk and enhance global shutter efficiency. | 03-27-2014 |
20140197301 | GLOBAL SHUTTER IMAGE SENSORS WITH LIGHT GUIDE AND LIGHT SHIELD STRUCTURES - An image sensor operable in global shutter mode may include an array of image pixels. Each image pixel may include a photodiode for detecting incoming light and a separate storage diode for temporarily storing charge. To maximize the efficiency of the image pixel array, image pixels may include light guide structures and light shield structures. The light guide structures may be used to funnel light away from the storage node and into the photodiode, while the light shield structures may be formed over storage nodes to block light from entering the storage nodes. The light guide structures may fill cone-shaped cavities in a dielectric layer, or the light guide structures may form sidewalls having a ring-shaped horizontal cross section. Metal interconnect structures in the dielectric layer may be arranged in concentric annular structures to form a near-field diffractive element that funnels light towards the appropriate photodiode. | 07-17-2014 |
20150060966 | IMAGE SENSORS WITH SILICIDE LIGHT SHIELDS - 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 a semiconductor substrate. Buried light shielding structures may be formed on 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 shields may be formed over conductive gate structures. A metal silicide layer may be formed to completely cover these conductive gate structures. Antireflective coating material may optionally be formed over the metal silicide layer. Forming gate structures with a metal silicide liner can help reduce optical pixel crosstalk and enhance global shutter efficiency. | 03-05-2015 |
20150062392 | IMAGE SENSORS WITH INTER-PIXEL LIGHT BLOCKING STRUCTURES - 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. | 03-05-2015 |