Abstract: An image sensor includes a plurality of photodiodes disposed in a semiconductor material to convert image light into image charge. A floating diffusion is disposed proximate to the plurality of photodiodes to receive the image charge from the plurality of photodiodes. A plurality of transfer transistors is coupled to transfer the image charge from the plurality of photodiodes into the floating diffusion in response to a voltage applied to the gate terminal of the plurality of transfer transistors. A first trench isolation structure extends from a frontside of the semiconductor material into the semiconductor material and surrounds the plurality of photodiodes. A second trench isolation structure extends from a backside of the semiconductor material into the semiconductor material. The second trench isolation structure is disposed between individual photodiodes in the plurality of photodiodes.

Abstract: An avalanche photodiode has a first diffused region of a first diffusion type overlying at least in part a second diffused region of a second diffusion type; and a first minority carrier sink region disposed within the first diffused region, the first minority carrier sink region of the second diffusion type and electrically connected to the first diffused region. In particular embodiments, the first diffusion type is N-type and the second diffusion type is P-type, and the device is biased so that a depletion zone having avalanche multiplication exists between the first and second diffused regions.

Abstract: An image sensor includes a plurality of photodiodes disposed in a semiconductor material to convert image light into image charge. A floating diffusion is disposed proximate to the plurality of photodiodes to receive the image charge from the plurality of photodiodes. A plurality of transfer transistors is coupled to transfer the image charge from the plurality of photodiodes into the floating diffusion in response to a voltage applied to the gate terminal of the plurality of transfer transistors. A first trench isolation structure extends from a frontside of the semiconductor material into the semiconductor material and surrounds the plurality of photodiodes. A second trench isolation structure extends from a backside of the semiconductor material into the semiconductor material. The second trench isolation structure is disposed between individual photodiodes in the plurality of photodiodes.

Abstract: A photon detection device includes a single photon avalanche diode (SPAD) disposed in a semiconductor layer. A guard ring structure is disposed in the semiconductor layer surrounding the SPAD to isolate the SPAD. A well region is disposed in the semiconductor layer surrounding the guard ring structure and disposed along an outside perimeter of the photon detection device. A contact region is disposed in the well region only in a corner region of the outside perimeter such that there is no contact region disposed along side regions of the outside perimeter. A distance between an inside edge of the guard ring structure and the contact region in the corner region of the outside perimeter is greater than a distance between the inside edge of the guard ring structure and the side regions of the outside perimeter such that an electric field distribution is uniform around the photon detection device.

Abstract: An image sensor includes a pixel array having plurality of pixel cells arranged into a plurality of rows and a plurality of columns of pixel cells in a first semiconductor die. A plurality of pixel support circuits are arranged in a second semiconductor die that is stacked and coupled together with the first semiconductor die. A plurality of interconnect lines are coupled between the first and second semiconductor dies, and each one of the plurality of pixel cells is coupled to a corresponding one of the plurality of pixel support circuits through a corresponding one plurality of interconnect lines. A plurality of shield bumps are disposed proximate to corners of the pixel cells in the pixel array and between the first and second semiconductor dies such that each one of the plurality of shield bumps is disposed between adjacent interconnect lines along a diagonal of the pixel array.

Abstract: An image sensor includes a semiconductor material including a photodiode disposed in the semiconductor material and an insulating material. A surface of the semiconductor material is disposed between the insulating material and the photodiode. The image sensor also includes isolation structures disposed in the semiconductor material and in the insulating material, and the isolation structures extend from within the semiconductor material through the surface and into the insulating material. The isolation structures include a core material and a liner material. The liner material is disposed between the core material and the semiconductor material, and is also disposed between the insulating material and the core material.

Abstract: An image sensor includes a semiconductor material including a photodiode disposed in the semiconductor material and an insulating material. A surface of the semiconductor material is disposed between the insulating material and the photodiode. The image sensor also includes isolation structures disposed in the semiconductor material and in the insulating material, and the isolation structures extend from within the semiconductor material through the surface and into the insulating material. The isolation structures include a core material and a liner material. The liner material is disposed between the core material and the semiconductor material, and is also disposed between the insulating material and the core material.

Abstract: A method of image sensor fabrication includes forming a photodiode and a floating diffusion in a first semiconductor material, and removing part of an oxide layer disposed proximate to a seed area on a surface of the first semiconductor material. The method also includes depositing a second semiconductor material over the surface of the first semiconductor material, and annealing the first semiconductor material and second semiconductor material. A portion of the second semiconductor material is etched away to form part of a source follower transistor, and dopant is implanted into the second semiconductor material to form a first doped region, a third doped region, and a second doped region. The second doped region is laterally disposed between the first doped region and the third doped region, and the second doped region is a channel of the source follower transistor.

Abstract: An avalanche photodiode has a first diffused region of a first diffusion type overlying at least in part a second diffused region of a second diffusion type; and a first minority carrier sink region disposed within the first diffused region, the first minority carrier sink region of the second diffusion type and electrically connected to the first diffused region. In particular embodiments, the first diffusion type is N-type and the second diffusion type is P-type, and the device is biased so that a depletion zone having avalanche multiplication exists between the first and second diffused regions.

Abstract: An image sensor includes a pixel array having plurality of pixel cells arranged into a plurality of rows and a plurality of columns of pixel cells in a first semiconductor die. A plurality of pixel support circuits are arranged in a second semiconductor die that is stacked and coupled together with the first semiconductor die. A plurality of interconnect lines are coupled between the first and second semiconductor dies, and each one of the plurality of pixel cells is coupled to a corresponding one of the plurality of pixel support circuits through a corresponding one plurality of interconnect lines. A plurality of shield bumps are disposed proximate to corners of the pixel cells in the pixel array and between the first and second semiconductor dies such that each one of the plurality of shield bumps is disposed between adjacent interconnect lines along a diagonal of the pixel array.

Abstract: An image sensor includes a plurality of photodiodes disposed in a semiconductor material between a first side and a second side of the semiconductor material. The image sensor also includes a plurality of hybrid deep trench isolation (DTI) structures disposed in the semiconductor material, where individual photodiodes in the plurality of photodiodes are separated by individual hybrid DTI structures. The individual hybrid DTI structures include a shallow portion that extends from the first side towards the second side of the semiconductor material, and the shallow portion includes a dielectric region and a metal region such that at least part of the dielectric region is disposed between the semiconductor material and the metal region. The hybrid DTI structures also include a deep portion that extends from the shallow portion and is disposed between the shallow portion and the second side of the semiconductor material.

Abstract: An image sensor includes a photodiode disposed in a first semiconductor material and a floating diffusion disposed proximate to the photodiode in the first semiconductor material. A source follower transistor is disposed in part in a second semiconductor material and includes: a first doped region, a third doped region, and a second doped region with an opposite polarity as the first doped region and the third doped region, and a gate electrode coupled to the floating diffusion and disposed in the first semiconductor material and aligned with the second doped region in the second semiconductor material of the source follower transistor.

Abstract: An avalanche photodiode sensor includes a plurality of avalanche photodiodes disposed in a semiconductor material where individual avalanche photodiodes in the plurality of avalanche photodiodes have an internal electric field parallel with a first surface of the semiconductor material. The individual avalanche photodiodes in the plurality of avalanche photodiodes include a p-doped semiconductor region which extends into the semiconductor material, and an n-doped semiconductor region which extends into the semiconductor material. The internal electric field extends between the p-doped semiconductor region and the n-doped semiconductor region. Processing methods as examples are also proposed.

Abstract: A photon detection device includes a single photon avalanche diode (SPAD) disposed in a semiconductor layer. A guard ring structure is disposed in the semiconductor layer surrounding the SPAD to isolate the SPAD. A well region is disposed in the semiconductor layer surrounding the guard ring structure and disposed along an outside perimeter of the photon detection device. A contact region is disposed in the well region only in a corner region of the outside perimeter such that there is no contact region disposed along side regions of the outside perimeter. A distance between an inside edge of the guard ring structure and the contact region in the corner region of the outside perimeter is greater than a distance between the inside edge of the guard ring structure and the side regions of the outside perimeter such that an electric field distribution is uniform around the photon detection device.

Abstract: An image sensor includes a plurality of photodiodes disposed proximate to a frontside of a first semiconductor layer to accumulate image charge in response to light directed into the frontside of the first semiconductor layer. A plurality of pinning wells is disposed in the first semiconductor layer. The pinning wells separate individual photodiodes included in the plurality of photodiodes. A plurality of dielectric layers is disposed proximate to a backside of the first semiconductor layer. The dielectric layers are tuned such that light having a wavelength substantially equal to a first wavelength included in the light directed into the frontside of the first semiconductor layer is reflected from the dielectric layers back to a respective one of the plurality of photodiodes disposed proximate to the frontside of the first semiconductor layer.

Abstract: Embodiments of an image sensor pixel that includes a photosensitive element, a floating diffusion region, and a transfer device. The photosensitive element is disposed in a substrate layer for accumulating an image charge in response to light. The floating diffusion region is dispose in the substrate layer to receive the image charge from the photosensitive element. The transfer device is disposed between the photosensitive element and the floating diffusion region to selectively transfer the image charge from the photosensitive element to the floating diffusion region. The transfer device includes a buried channel device including a buried channel gate disposed over a buried channel dopant region. The transfer device also includes a surface channel device including a surface channel gate disposed over a surface channel region. The surface channel device is in series with the buried channel device. The surface channel gate has the opposite polarity of the buried channel gate.

Abstract: An improved back side illuminated (BSI) complementary metal oxide semiconductor (CMOS) image sensor, and associated methods, improve phase detecting capability. The BSI CMOS image sensor has an array of pixels that include a phase detecting pixel (PDP), a composite grid formed of a buried color filter array and composite metal/oxide grid, and a photodiode implant corresponding to the PDP. A PDP mask is fabricated with a deep trench isolation (DTI) structure proximate the PDP and positioned to mask at least part of the photodiode implant such that the PDP mask is positioned between the composite grid and the photodiode implant.

Abstract: An image sensor includes a plurality of photodiodes disposed proximate to a frontside of a first semiconductor layer to accumulate image charge in response to light directed into the frontside of the first semiconductor layer. A plurality of pinning wells is disposed in the first semiconductor layer. The pinning wells separate individual photodiodes included in the plurality of photodiodes. A plurality of dielectric layers is disposed proximate to a backside of the first semiconductor layer. The dielectric layers are tuned such that light having a wavelength substantially equal to a first wavelength included in the light directed into the frontside of the first semiconductor layer is reflected from the dielectric layers back to a respective one of the plurality of photodiodes disposed proximate to the frontside of the first semiconductor layer.

Abstract: An imaging device includes a semiconductor substrate having a photosensitive element for accumulating charge in response to incident image light. The semiconductor substrate includes a light-receiving surface positioned to receive the image light. The imaging device also includes a negative charge layer and a charge sinking layer. The negative charge layer is disposed proximate to the light-receiving surface of the semiconductor substrate to induce holes in an accumulation zone in the semiconductor substrate along the light-receiving surface. The charge sinking layer is disposed proximate to the negative charge layer and is configured to conserve or increase an amount of negative charge in the negative charge layer. The negative charge layer is disposed between the semiconductor substrate and the charge sinking layer.

Abstract: A method for manufacturing a backside illuminated color image sensor includes (a) modifying the frontside of an image sensor wafer, having pixel arrays, to produce electrical connections to the pixel arrays, wherein the electrical connections extend depth-wise into the image sensor wafer from the frontside, and (b) modifying the backside of the image sensor wafer to expose the electrical connections.