Abstract: A semiconductor device that includes a metal pad buried in the semiconductor substrate that is electrically connected to a metal interconnection structure and electrically isolated from the semiconductor substrate. The semiconductor substrate forms an opening that extends from a back surface to the metal pad. A method for manufacturing a semiconductor device with buried metal pad including depositing, in a recess of a semiconductor substrate, a metal pad, isolating the pad from the substrate, electrically connecting the metal pad to the frontside of the substrate and connecting the metal pad to the backside of the substrate with an opening. A method for stabilizing through-silicon via connections in semiconductor device including electrically coupling a metal interconnection structure to a metal pad submerged in a semiconductor substrate and forming a through-silicon via into the semiconductor substrate that contacts the metal pad.

Abstract: A flare-suppressing image sensor includes a first pixel formed in a substrate and a refractive element located above the first pixel. The refractive element has, with respect to a top surface of the substrate, a height profile having at least two one-dimensional local maxima in each of a first cross-sectional plane and a second cross-sectional plane perpendicular to the first cross-sectional plane. Each of the first and second cross-sectional planes is perpendicular to the top surface and intersects the first pixel.

Abstract: A comparator includes a first stage including a first output to generate a first output signal that transitions between an upper and lower voltage level in response to a comparison of first and second inputs of the first stage. A second stage includes an input coupled to receive the first output signal from the first output of the first stage, and a second output configured to generate a second output signal in response to the first output signal. A clamp circuit includes a first node and a second node. The first node is coupled to the first output of the first stage and the second node is coupled to a supply voltage. The clamp circuit is configured to clamp a voltage difference between the first node and the second node to clamp a voltage swing of the first output signal.

Abstract: An imaging device includes a photodiode array including a 2×2 grouping of N×N groupings of photodiodes. Each N×N grouping includes N2?1 image sensing photodiodes and a single phase detection autofocus (PDAF) photodiode that is arranged proximate to a center of the 2×2 grouping. A shared floating diffusion is coupled to each photodiode of a respective N×N grouping of photodiodes. An analog to digital converter (ADC) is configured to generate a reference readout in response to charge in the shared floating diffusion after a reset operation. The ADC is next configured to generate a PDAF readout in response to charge transferred from the single PDAF photodiode to the shared floating diffusion. The ADC is then configured to generate a combined readout in response to charge transferred from the image sensing photodiodes combined with the charge transferred previously from the single PDAF photodiode in the shared floating diffusion.

Abstract: An image sensor includes a substrate having a plurality of small photodiodes and a plurality of large photodiodes surrounding the small photodiodes. The substrate further includes a plurality of deep trench isolation structures in regions of the substrate between ones of the small photodiodes and the large photodiodes. Each of large photodiodes having a full well capacity larger than each of the small photodiodes. The image sensor further includes an array of color filters disposed over the substrate, a first and second buffer layer disposed between the substrate and the array of color filters, metal grid structures disposed between the color filters and above the first buffer layer, and an attenuation layer portion above a region of the substrate between ones of the large and small photodiodes, the attenuation layer portion is between the first and second buffer layers and normal to an upper surface of the substrate.

Abstract: An image sensor with quantum efficiency enhanced by inverted pyramids includes a semiconductor substrate and a plurality of microlenses. The semiconductor substrate includes an array of pixels. Each of the pixels is configured to convert light incident on the pixel to an electrical output signal, the semiconductor substrate having a top surface for receiving the light. The top surface forms a plurality of inverted pyramids in each pixel. The plurality of microlenses are disposed above the top surface and aligned to the plurality of inverted pyramids, respectively.

Abstract: An imaging device includes a photodiode array. The photodiodes include a first set of photodiodes configured as image sensing photodiodes and a second set of photodiodes configured as phase detection auto focus (PDAF) photodiodes. The PDAF photodiodes are arranged in at least pairs in neighboring columns and are interspersed among the image sensing photodiodes. Transfer transistors are coupled to corresponding photodiodes. The transfer transistors coupled to the image sensing photodiodes included in an active row of are controlled in response to a first transfer control signal or a second transfer control signal that control all of the image sensing photodiodes of the active row. A transfer transistor is coupled to one of a pair of the PDAF photodiodes of the active row. The first transfer transistor is controlled in response to a first PDAF control signal that is independent of the first or second transfer control signals.

Abstract: A pixel cell includes a photodiode buried beneath a first side of semiconductor material and coupled to photogenerate image charge in response to incident light. A transfer gate is disposed over the photodiode and includes a vertical transfer gate portion extending a first distance from the first side into the semiconductor material. A floating diffusion region is disposed in the semiconductor material proximate to the transfer gate and is coupled to transfer the image charge from the photodiode toward the first side of the semiconductor material and into the floating diffusion region in response to a transfer control signal. A first pixel transistor having a first gate is disposed over the photodiode proximate to the first side of the semiconductor material. The first gate has a ring structure laterally surrounding the floating diffusion region and the transfer gate at the first side of the semiconductor material.

Abstract: An imaging device includes a first pixel circuit having a first plurality of photodiodes that includes a phase detection autofocus photodiode with image sensing photodiodes. A first buffer transistor having a first threshold voltage is coupled to the first plurality of photodiodes to generate a first output signal. A second pixel circuit is included having a second plurality of photodiodes that are all image sensing photodiodes. A second buffer transistor having a second threshold voltage is coupled to the second plurality of photodiodes to generate a second output signal. The first threshold voltage is less than the second threshold voltage. A driver is coupled to receive a combination of the first and second output signals to generate a total output signal. An influence of the first output signal dominates the second output signal in the total output signal because the first threshold voltage is less than the second threshold voltage.

Abstract: A pixel circuit includes a photodiode, a floating diffusion, and a conduction gate channel of a multi-gate transfer block disposed in a semiconductor material layer. The multi-gate transfer block is coupled to the photodiode, the floating diffusion, and an overflow capacitor. The multi-gate transfer block also includes first, second, and third gates that are disposed proximate to the single conduction gate channel region. The conduction gate channel is a single region shared among the first, second, and third gates. Overflow image charge generated in the photodiode leaks from the photodiode into the conduction gate channel to the overflow capacitor in response to the first gate, which is coupled between the photodiode and the conduction gate channel, receiving a first gate OFF signal and the second gate, which is coupled between the conduction gate channel and the overflow capacitor, receiving a second gate ON signal.

Abstract: A pixel cell includes a photodiode disposed in a pixel cell region and proximate to a front side of a semiconductor layer to generate image charge in response to incident light directed through a backside to the photodiode. A cell deep trench isolation (CDTI) structure is disposed in the pixel cell region along an optical path of the incident light to the photodiode and proximate to the backside. The CDTI structure includes a central portion extending a first depth from the backside towards the front side. Planar outer portions extend laterally outward from the central portion. The planar output portions further extend a second depth from the backside towards the front side. The first depth is greater than the second depth. Planes formed by each of the planar outer portions intersect in a line coincident with a longitudinal center line of the central portion of the CDTI structure.

Abstract: A lens-array imager includes lenses Lm forming a lens array having a pitch dx, a pixel array including pixel-array regions Rm, and apertured baffle-layers therebetween; m={0, 1, 2, . . . }. Each pixel-array region has a width rx<dx and pitch px<dx. Each apertured baffle-layer is at a respective distance zk from the pixel array and has a respective plurality of aperture stops Am forming an aperture-stop array. A center of each aperture stop Am is collinear with both a center of region Rm and an optical center of lens Lm. Each aperture-stop array has a pitch that approaches px as zk approaches zero and approaches lens pitch dx as zk approaches a distance zL between lens L0 and region R0. A width of each aperture stop Am has an upper limit that increases from px, when zk equals zero, to Wx when distance zk equals zL.

Abstract: An image sensor pixel array comprises a plurality of image pixel units to gather image information and a plurality of phase detection auto-focus (PDAF) pixel units to gather phase information. Each of the PDAF pixel units includes two of first image sensor pixels covered by two micro-lenses, respectively. Each of the image pixel units includes four of second image sensor pixels adjacent to each other, wherein each of the second image sensor pixels is covered by an individual micro-lens. A coating layer is disposed on the micro-lenses and forms a flattened surface across the whole image sensor pixel array. A PDAF micro-lens is formed on the coating layer to cover the first image sensor pixels.

Abstract: A pixel includes a semiconductor substrate, a photodiode region, a floating diffusion region, and a dielectric layer. The substrate has a top surface forming a trench lined by the dielectric layer, and having a trench depth relative to a planar region of the top surface. The photodiode region is in the substrate and includes a bottom photodiode section beneath the trench and a top photodiode section adjacent to the trench, adjoining the bottom photodiode section, and extending toward the planar region to a photodiode depth less than the trench depth. The floating diffusion region is adjacent to the trench and has a junction depth less than the trench depth. A top region of the dielectric layer is between the planar region and the junction depth. A bottom region of the dielectric layer is between the photodiode depth and the trench depth, and thicker than the top region.

Abstract: A pixel cell readout circuit includes an amplifier and a capacitor switch circuit that includes a first routing path coupled to an input of the amplifier. A second routing path includes switches coupled in series along the second routing path. A first end of the second routing path is coupled to a bitline. A second end of the second routing path is coupled to an output of the amplifier. Only one of the switches is turned off and a remainder of the switches are turned on. Capacitors are coupled in parallel between the first routing path and the second routing path. A first end of each of the capacitors is coupled to the first routing path. A second end of each of the capacitors is coupled to the second routing path. The switches are interleaved among the second ends of the capacitors along the second routing path.

Abstract: A shallow trench isolation (STI) structure and method of fabrication includes a two-step epitaxial growth process. A trench larger than the target STI structure is etched into a semiconductor substrate, a first layer of un-doped semiconductor material epitaxially grown in the trench to provide an STI structure having a target depth and a critical dimension, and a second layer of doped semiconductor material epitaxially grown on the first layer, said second layer filling the trench and forming a protrusion above the front-side of the semiconductor substrate.

Abstract: A pixel includes a semiconductor substrate, an upper surface thereof forming a trench having a trench depth relative to a planar region of the upper surface surrounding the trench, and in a plane perpendicular to the planar region; an upper width between the planar region and an upper depth that is less than the trench depth; and a lower width, between the upper depth and the trench depth, that is less than the upper width. A floating diffusion region adjacent to the trench extends away from the planar region to a junction depth exceeding the upper depth and is less than the trench depth. The photodiode region in the substrate includes a lower photodiode section beneath the trench and an upper photodiode section adjacent to the trench, beginning at a photodiode depth that is less than the trench depth, extending toward and adjoining the lower photodiode section.

Abstract: A method of fabricating a target shallow trench isolation (STI) structure between devices in a wafer-level image sensor having a large number of pixels includes etching a trench, the trench having a greater depth and width than a target STI structure and epitaxially growing the substrate material in the trench for a length of time necessary to provide the target depth and width of the isolation structure. An STI structure formed in a semiconductor substrate includes a trench etched in the substrate having a depth and width greater than that of the STI structure, and semiconductor material epitaxially grown in the trench to provide a critical dimension and target depth of the STI structure. An image sensor includes a semiconductor substrate, a photodiode region, a pixel transistor region and an STI structure between the photodiode region and the pixel transistor region.

Abstract: A structure light module comprises: a VCSEL substrate comprising a VCSEL array comprising a plurality of individual VCSELs; a first spacer disposed on the VCSEL substrate; a first wafer level lens comprising a glass substrate and at least a replicated lens on a first surface of the glass substrate disposed on the first spacer; a FOE disposed on the first wafer level lens; a second spacer disposes on the FOE; a second wafer level lens comprising a glass substrate and at least a replicated lens on a first surface of the glass substrate disposed on the second spacer; a third spacer disposed on the second wafer level lens; a DOE disposed on the third spacer, where a structure light is projected from the DOE on a target surface for 3D imaging.

Abstract: An imaging device includes groupings of photodiodes having four photodiodes. A transfer transistor is between each photodiode and a floating diffusion. Each floating diffusion is coupled to up to two photodiodes per grouping at a time through transfer transistors. A buffer transistor is coupled to each floating diffusion. The buffer transistors may be in a first or second grouping of buffer transistors. A first bit line is coupled to up to two buffer transistors of the first grouping and a second bit line is coupled to up to two buffer transistors of the second grouping of buffer transistors at a time. A color filter array including a plurality of groupings of color filters is disposed over respective photodiodes of the photodiode array, wherein each grouping of color filters includes four color filters having a same color, wherein each grouping of color filters overlaps two groupings of photodiodes.