Semiconductor Components Industries, LLC

Aptina Imaging Corporation

Andrew Eugene Perkins

Marc Allen Sulfridge

Swarnal Borthakur

Ulrich C Boettiger

Kevin W Hutto

Rickie C Lake

Marko Mlinar

Rick C Lake

Scott Donald Churchwell

Bartosz Piotr Banachowicz

Jonathan Michael Stern

Nathan Lee

An imaging device may include single-photon avalanche diodes (SPADs). To improve the sensitivity and signal-to-noise ratio of the SPADs, light scattering structures may be formed in the semiconductor substrate to increase the path length of incident light through the semiconductor substrate. The light scattering structures may include a low-index material formed in trenches in the semiconductor substrate. One or more microlenses may focus light onto the semiconductor substrate. Areas of the semiconductor substrate that receive more light from the microlenses may have a higher density of light scattering structures to optimize light scattering while mitigating dark current.

Semiconductor devices with single-photon avalanche diodes and light scattering structures

Semiconductor devices with single-photon avalanche diodes and light scattering structures with different densities

A semiconductor wafer has a plurality of non-rectangular semiconductor die with an image sensor region. The non-rectangular semiconductor die has a circular, elliptical, and shape with non-linear side edges form factor. The semiconductor wafer is singulated with plasma etching to separate the non-rectangular semiconductor die. A curved surface is formed in the image sensor region of the non-rectangular semiconductor die. The non-rectangular form factor effectively removes a portion of the base substrate material in a peripheral region of the semiconductor die to reduce stress concentration areas and neutralize buckling in the curved surface of the image sensor region. A plurality of openings or perforations can be formed in a peripheral region of a rectangular or non-rectangular semiconductor die to reduce stress concentration areas and neutralize buckling. A second semiconductor die can be formed in an area of the semiconductor wafer between the non-rectangular semiconductor die.

Semiconductor device and method of forming curved image sensor region robust against buckling

An imaging system may include an image sensor with phase detection pixel groups for depth sensing or automatic focusing operations. Each phase detection pixel group may have two or more photosensitive regions covered by a single microlens so that each photosensitive region has an asymmetric angular response. The image sensor may be sensitive to both near-infrared (NIR) and visible light. Each phase detection pixel group may be designed to include light-scattering structures that increase NIR sensitivity while minimizing disruptions of phase detection and visible light performance. Deep trench isolation may be formed between adjacent photosensitive areas within the phase detection pixel group. The light-scattering structures may have a non-uniform distribution to minimize disruptions of phase detection performance.

Image sensor with near-infrared and visible light phase detection pixels

A method for forming curved image sensors may include applying positive pressure to the face of an image sensor, forcing the image sensor to adhere the curved surface of a substrate. The pressure may be applied to the face of the image sensor in a variety of ways, including using pneumatic pressure, hydraulic pressure, or pressure from an elastic or inelastic solid. Processing may occur on either a single image sensor die or an image sensor wafer. When an image sensor wafer is processed, a substrate may be used that has a number of cavities defined by respective curved surfaces with each cavity corresponding to a respective image sensor. When pressure is applied to the image sensor, the image sensor may deform until the curvature of the image sensor matches the curvature of the curved surface of the underlying substrate.

Methods of forming curved image sensors

An image sensor may include a pixel array with high dynamic range functionality and phase detection pixels. The phase detection pixels may be arranged in phase detection pixel groups. Each phase detection pixel group may include three adjacent pixels arranged consecutively in a line. A single microlens may cover all three pixels in the phase detection pixel group, or two microlenses may combine to cover the three pixels in the phase detection pixel group. The edge pixels in each phase detection pixel group may have the same integration time and the same color. The middle pixel in each phase detection pixel group may have the same or different color as the edge pixels, and the same or different integration time as the edge pixels. Phase detection pixel groups may also be formed from two pixels that each are 1.5 times the size of neighboring pixels.

Imaging systems with high dynamic range and phase detection pixels

Methods for forming backside illuminated (BSI) image sensors having metal redistribution layers (RDL) and solder bumps for high performance connection to external circuitry are provided. In one embodiment, a BSI image sensor with RDL and solder bumps may be formed using a temporary carrier during manufacture that is removed prior to completion of the BSI image sensor. In another embodiment, a BSI image sensor with RDL and solder bumps may be formed using a permanent carrier during manufacture that partially remains in the completed BSI image sensor. A BSI image sensor may be formed before formation of a redistribution layer on the front side of the BSI image sensor. A redistribution layer may, alternatively, be formed on the front side of an image wafer before formation of BSI components such as microlenses and color filters on the back side of the image wafer.

Methods for forming backside illuminated image sensors with front side metal redistribution layers

An image sensor die may include a pixel array formed in an image sensor substrate and covered by a transparent cover layer. The transparent cover layer may be attached to the image sensor substrate using adhesive. Electrical interconnect structures such as conductive vias may be formed in the transparent cover layer and may be used in conveying electrical signals between the image sensor and a printed circuit board. The conductive vias may have one end coupled to a bond pad on the upper surface of the transparent cover layer and an opposing end coupled to a bond pad on the upper surface of the image sensor substrate. The conductive vias may pass through openings that extend through the transparent cover layer and the adhesive. Conductive structures such as wire bonds, stud bumps, or solder balls may be coupled to the bond pads on the surface of the transparent cover layer.

Image sensors with interconnects in cover layer

An imaging system may include an image sensor having an array of pixels. The image sensor may include an array of microlenses formed over a substrate and an array of color filter elements interposed between the microlenses and the substrate. Dielectric wall structures may be interposed between the color filter elements. Light shield structures may be formed within or on the dielectric wall structures and may be used to reduce optical crosstalk between adjacent pixels. The light shield structures may be formed on opposing sides or corners of the color filter elements and may partially or fully extend along the height of the color filter elements. In some arrangements, the light shield structures may each have a vertical portion that contacts a side surface of an adjacent color filter element and a horizontal portion that contacts a lower surface of an adjacent color filter element.

Imaging systems with integrated light shield structures

Methods for forming backside illuminated image sensors with front side metal redistribution layers and a permanent carrier layer

An array of color filter elements may be formed over an array of photodiodes in an integrated circuit for an imaging device using a carrier substrate. The carrier substrate may have a planar surface with a release layer. A layer of color filter material may be applied to the release layer. The carrier substrate may then be flipped and the layer of color filter material may be bonded to the integrated circuit. Heat may be applied to activate the release layer and the carrier substrate may be removed at the interface between the release layer and the color filter material. The layer of color filter material may be patterned either before bonding the layer of color filter material or after the carrier substrate is removed. A layer of microlenses may be formed over the array of color filter elements using a carrier substrate.

Methods of forming imaging device layers using carrier substrates

An image sensor unit may have a backside-illuminated imager and an image co-processor stacked together. The image co-processor may be mounted in a cavity in a permanent carrier. The permanent carrier may include fluid channels that allow cooling fluid to flow past the image co-process and past the imager, thereby removing excess heat generated by the image sensor unit during operation.

Backside illuminated image sensors with stacked dies

A method for fabricating semiconductor components with lens structures and lens support structures includes the steps of providing semiconductor substrates on a substrate, attaching a carrier to the substrate configured to support the substrate during various processes, thinning the carrier to form lens support structures having desired geometrical characteristics, singulating the substrate and the carrier such that each semiconductor substrate includes a lens support structure, and then attaching the lens structures to the support structures. Each semiconductor component includes a thinned semiconductor substrate, a support structure attached to the semiconductor substrate, and a lens structure attached to the support structure. A system for fabricating the semiconductor components includes the substrate containing the semiconductor substrates, and the carrier configured to support the wafer, to protect the semiconductor substrates and to provide the lens support structures.

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Boise, ID, United States of America

Andrew Eugene Perkins