Omnivision Technologies, Inc.

Young Woo Jung

Chih-Wei Hsiung

Vincent Venezia

Lindsay Alexander Grant

Kazufumi Watanabe

Dyson Hsinchih Tai

Seong Yeol Mun

Zhiqiang Lin

Wei Zheng

Sang Joo Lee

Geunsook Park

Electrical Phase Detection Auto Focus. In one embodiment, an image sensor includes a plurality of pixels arranged in rows and columns of a pixel array disposed in a semiconductor material. Each pixel includes a plurality of photodiodes configured to receive incoming light through an illuminated surface of the semiconductor material. The plurality of pixels includes at least one autofocusing phase detection (PDAF) pixel having: a first subpixel without a light shielding, and a second subpixel without the light shielding. Autofocusing of the image sensor is at least in part determined based on different electrical outputs of the first subpixel and the second sub pixels.

Electrical phase detection auto focus

Methods of forming transistors include providing a substrate material, forming a recess to a first depth in the substrate material, the recess corresponding to a gate region and extending in a channel length direction and a channel width direction that is perpendicular to the channel length direction, forming a trench structure in the substrate material by deepening the recess to a second depth using an isotropic process, forming an isolation layer on the substrate material, forming a gate portion of the isolation layer on the substrate material such that the gate portion of the isolation layer extends into the trench structure, and forming a gate on the isolation layer such that the gate extends into the trench structure.

Transistor having increased effective channel width

Backside illuminated sensor pixel structure. In one embodiment, and image sensor includes a plurality of pixels arranged in rows and columns of a pixel array that are disposed in a semiconductor substrate. Individual photodiodes of the pixel array are configured to receive an incoming light through a backside of the semiconductor substrate. A front side of the semiconductor substrate is opposite from the backside. A plurality of transistors disposed proximate to the front side of the semiconductor substrate, are arranged in a row along an outer perimeter of the photodiodes of the respective pixel; and a plurality of isolation structures arranged to bracket the row of transistors along the outer perimeter of the photodiodes. A plurality of contacts electrically contacting the plurality of isolation structures, and the contacts are configured to voltage-bias the plurality of isolation structures.

Negatively biased isolation structures for pixel devices

Image sensors include a photodiode formed in a substrate material and a transistor coupled to the photodiode. The transistor has a trench structure formed in the substrate material, an isolation layer disposed on the substrate material, and a gate disposed on the isolation layer and extending into the trench structure. The trench structure has a polygonal cross section in a channel width plane, the polygonal cross section defining at least four sidewall portions of the substrate material, which contribute to an effective channel width measured in the channel width plane that is wider than a planar channel width of the transistor.

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.

Image sensor with dual trench isolation structures at different isolation structure depths

An image sensor includes a photodiode disposed in a semiconductor material to generate image charge in response to incident light, and a floating diffusion disposed in the semiconductor material proximate to the photodiode. A transfer transistor is coupled to the photodiode to transfer the image charge from the photodiode into the floating diffusion in response to a transfer signal applied to a transfer gate of the transfer transistor. A source follower transistor is coupled to the floating diffusion to amplify a charge on the floating diffusion. The source follower transistor includes a gate electrode including a semiconductor material having a first dopant type; a source electrode, having a second dopant type, disposed in the semiconductor material; a drain electrode, having the second dopant type, disposed in the semiconductor material; and a channel, having the second dopant type, disposed between the source electrode and the drain electrode.

Source follower device for enhanced image sensor performance

A phase detection autofocus image sensor includes a first photodiode in a plurality of photodiodes disposed in a semiconductor material and a second photodiode in the plurality of photodiodes. A first pinning well is disposed between the first photodiode and the second photodiode, and the first pinning well includes a first trench isolation structure that extends from a first surface of the semiconductor material into the semiconductor material a first depth. A second trench isolation structure is disposed in the semiconductor material and surrounds the first photodiode and the second photodiode. The second trench isolation structure extends from the first surface of the semiconductor material into the semiconductor material a second depth, and the second depth is greater than the first depth.

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San Jose, CA, United States of America

Young Woo Jung