摘要:
A pixel array comprises a plurality of photo-sensitive elements arranged in rows and columns and readout circuitry for reading a value of a photo-sensitive element. Shared readout circuitry is provided for a pair of adjacent photo-sensitive elements. Adjacent instances of the shared readout circuitry are staggered with respect to one another. For a layout having shared readout circuitry for a pair of photo-sensitive elements, adjacent instances of the shared readout circuitry are offset by a horizontal distance of one column and a vertical distance of one row of the array. The shared readout circuitry can serve a pair of adjacent photo-sensitive elements in a row or column of the array, or a pair of photo-sensitive elements which are diagonally adjacent in the array. An improved yield and symmetry results from staggering instances of the shared readout circuitry.
摘要:
A pixel comprises a photo-sensitive element for generating charges in response to incident radiation and a sense node. A transfer gate is positioned between the photo-sensitive element and the sense node for controlling transfer of charges to the sense node. A reset switch is connected to the sense node for resetting the sense node to a predetermined voltage. A first buffer amplifier has an input connected to the sense node. A sample stage is connected to the output of the first buffer amplifier and is operable to sample a value of the sense node. A second buffer amplifier has an input connected to the sample stage. Control circuitry operates the reset switch and causes the sample stage to sample the sense node while the photo-sensitive element is being exposed to radiation. An array of pixels is synchronously exposed to radiation. Sampled values for a first exposure period can be read while the photo-sensitive element is exposed for a second exposure period.
摘要:
A pixel array includes a plurality of pixel structures, with each pixel structure having a photo-sensitive element for generating charge in response to incident light; a charge conversion element; a first transfer gate and a second transfer gate connected in series between the photosensitive element and the charge conversion element or between the photosensitive element and a supply line; and an output stage. A first transfer gate control line is connected to the first transfer gates of a first sub-set of the pixel structures in the array; and a second transfer gate control line connected to the second transfer gates of a second sub-set of the pixel structures in the array. The first sub-set of pixel structures and second sub-set of pixel structures partially overlap, having at least one pixel structure in common between them.
摘要:
A method of manufacturing a backside illuminated image sensor includes providing a start material that has a layer of semiconductor material on a substrate. The layer of semiconductor material has a first face and a second, backside, face. The layer of semiconductor material is processed to form semiconductor devices in the layer adjacent the first face. At least a part of the substrate is removed to leave an exposed face. A passivation layer is formed on the exposed face, the passivation layer having negative fixed charges. The passivation layer can be Al2O3 (Sapphire). The passivation layer can have a thickness less than 5 μm, advantageously less than 1 μm, and more advantageously in the range 1 nm-150 nm. Another layer, or layers, can be provided on the passivation layer, including: an anti-reflective layer, a layer to improve passivation, a layer including a color filter pattern, a layer comprising a microlens.