Abstract: The present invention relates to a method of manufacturing a backside illumination (BSI) CMOS optical sensor and more specifically to a method of reducing the cross talk and enhance the photon detection efficiency (PDE) in a backside illumination (BSI) CMOS optical sensor. In particular the claimed method comprises the step of creating an isolation structure between the adjacent sensing elements of the pixel-array of said BSI CMOS optical sensor, so as to isolate all the adjacent sensing elements from each other, and the step of creating a common voltage backside applying structure to all the sensing elements of said pixel-array, so as to connect all the sensing elements to a common voltage bias.

Abstract: This disclosure provides a semiconductor sensor of ionizing radiation and/or ionizing particles with a backside bias electrode and a backside junction for completely depleting the semiconductor substrate up to carrier collection regions each connected to a respective collection electrode of carriers generated by ionization in the substrate. Differently from prior sensors, the sensor of this disclosure has an intermediate semiconductor layer formed upon the substrate, having a greater doping concentration than the doping concentration of the substrate and a doping of a same type. In this intermediate layer, buried doped regions of opposite type one separated from the other are formed for shielding superficial regions in which readout circuits are defined.

Abstract: This disclosure provides a semiconductor sensor of ionizing radiation and/or ionizing particles with a backside bias electrode and a backside junction for completely depleting the semiconductor substrate up to carrier collection regions each connected to a respective collection electrode of carriers generated by ionization in the substrate. Differently from prior sensors, the sensor of this disclosure has an intermediate semiconductor layer formed upon the substrate, having a greater doping concentration than the doping concentration of the substrate and a doping of a same type. In this intermediate layer, buried doped regions of opposite type one separated from the other are formed for shielding superficial regions in which readout circuits are defined.

Abstract: A method for manufacturing a CMOS image sensor for near infrared detection. The method includes: a) providing a silicon wafer; b) performing a germanium implantation in a portion of a front side of the silicon wafer; c) performing an annealing so as to cause thermal diffusion of implanted germanium species, thereby forming silicon-germanium alloy lattice in a first silicon-germanium region exposed on the front side of the silicon wafer; d) carrying out the steps b) and c) one or more times; and e) forming first photodetector active areas in portions of the first silicon-germanium region downwards extending from the front side of the silicon wafer, wherein said first photodetector active areas are sensitive to both near infrared and visible radiations. The first photodetector active areas are formed also in portions of the silicon wafer extending below said portions of the first silicon-germanium region.

Abstract: The present invention concerns a method (1) for manufacturing a CMOS image sensor (2; 3) for near infrared detection. Said method (1) includes: a) providing a silicon wafer (20); b) performing a germanium implantation in a portion of a front side of the silicon wafer (24); c) performing an annealing so as to cause thermal diffusion of implanted germanium species, thereby forming silicon-germanium alloy lattice in a first silicon-germanium region (27) exposed on the front side of the silicon wafer (24); d) carrying out the steps b) and c) one or more times; and e) forming first photodetector active areas (28) in portions of the first silicon-germanium region (27) downwards extending from the front side of the silicon wafer (24), wherein said first photodetector active areas (28) are sensitive to both near infrared and visible radiations.

Abstract: An optical sensor based on CMOS technology including a semiconductor substrate; an array of photocells, each of which includes a respective photodetector active area that is formed in and exposed on a given planar surface of said semiconductor substrate; a multilayer structure that includes metal and dielectric layers and is formed on the given planar surface; and light shielding means formed in or on the multilayer structure; wherein each photodetector active area is associated with a corresponding optical path extending through the light shielding means and directed towards said photodetector active area. All the photocells are connected in parallel to provide an overall output electrical signal related to incident light impinging on the photodetector active areas. All the optical paths are parallel to a given direction thereby causing all the photodetector active areas to be reached by incident light with incident direction parallel to said given direction.

Abstract: The present invention relates to an optical sensor that is formed in an integrated circuit based on CMOS technology and that comprises: one or more photocells including one or more photodetector active areas and an optical stack formed on the photodetector active area(s); and light shielding means, that are formed in or on the optical stack, and are configured, for each photocell, to define an angular range around a given incident direction with respect to said photocell, block incident light with incidence angle outside the defined angular range, and allow incident light with incidence angle within the defined angular range to propagate through the optical stack down to a respective photodetector active area; whereby the light shielding means limit angular response of the optical sensor.

Abstract: Image sensors may include a plurality of photodiodes. The photodiodes may be isolated from each other using isolations regions formed from p-well or n-well implants. Deep and narrow isolation regions may be formed using a multi-step process that selectively places implants at desired depths in a substrate. If desired, the multi-step process may include only one photolithographic patterning step, which in turn can help reduce costs, fabrication time, and alignment errors. The process may include passing ions through a stack of alternating layers of material such as alternating layers of oxide and nitride. After each implant, a layer in the stack may be removed and ions may be passed through the layers remaining in the stack to form an implant at a different depth in the substrate.

Abstract: Methods and devices that incorporate microlens arrays are disclosed. An image sensor includes a pixel layer and a dielectric layer. The pixel layer has a photodetector portion configured to convert light absorbed by the pixel layer into an electrical signal. The dielectric layer is formed on a surface of the pixel layer. The dielectric layer has a refractive index that varies along a length of the dielectric layer. A method for fabricating an image sensor includes forming an array of microlenses on a surface of the dielectric layer, emitting ions through the array of microlenses to implant the ions in the dielectric layer, and removing the array of microlenses from the surface of the dielectric layer.

Abstract: Image sensors may include a plurality of photodiodes. The photodiodes may be isolated from each other using isolations regions formed from p-well or n-well implants. Deep and narrow isolation regions may be formed using a multi-step process that selectively places implants at desired depths in a substrate. If desired, the multi-step process may include only one photolithographic patterning step, which in turn can help reduce costs, fabrication time, and alignment errors. The process may include passing ions through a stack of alternating layers of material such as alternating layers of oxide and nitride. After each implant, a layer in the stack may be removed and ions may be passed through the layers remaining in the stack to form an implant at a different depth in the substrate.

Abstract: Methods and devices that incorporate microlens arrays are disclosed. An image sensor includes a pixel layer and a dielectric layer. The pixel layer has a photodetector portion configured to convert light absorbed by the pixel layer into an electrical signal. The dielectric layer is formed on a surface of the pixel layer. The dielectric layer has a refractive index that varies along a length of the dielectric layer. A method for fabricating an image sensor includes forming an array of microlenses on a surface of the dielectric layer, emitting ions through the array of microlenses to implant the ions in the dielectric layer, and removing the array of microlenses from the surface of the dielectric layer.

Abstract: Methods and devices that incorporate microlens arrays are disclosed. An image sensor includes a pixel layer and a dielectric layer. The pixel layer has a photodetector portion configured to convert light absorbed by the pixel layer into an electrical signal. The dielectric layer is formed on a surface of the pixel layer. The dielectric layer has a refractive index that varies along a length of the dielectric layer. A method for fabricating an image sensor includes forming an array of microlenses on a surface of the dielectric layer, emitting ions through the array of microlenses to implant the ions in the dielectric layer, and removing the array of microlenses from the surface of the dielectric layer.

Abstract: Methods and devices that incorporate microlens arrays are disclosed. An image sensor includes a pixel layer and a dielectric layer. The pixel layer has a photodetector portion configured to convert light absorbed by the pixel layer into an electrical signal. The dielectric layer is formed on a surface of the pixel layer. The dielectric layer has a refractive index that varies along a length of the dielectric layer. A method for fabricating an image sensor includes forming an array of microlenses on a surface of the dielectric layer, emitting ions through the array of microlenses to implant the ions in the dielectric layer, and removing the array of microlenses from the surface of the dielectric layer.

Abstract: Imager sensor pixels, image sensor and methods for forming image sensors. An image sensor pixel includes a photosensor, a microlens that receives incident light, at least one fabrication layer between the photosensor and the microlens and a passivation layer between the microlens and the at least one fabrication layer. The passivation layer includes a plurality of impurities and passes the incident light from the microlens to the photosensor without substantially redirecting the incident light.