Omnivision Technologies, Inc.

Hsin-Chih Tai

Duli Mao

Howard E Rhodes

Vincent Venezia

Yin Qian

Gang Chen

Sohei Manabe

Ashish A Shah

Keh-Chiang Ku

Wei Zheng

Tiejun Dai

Sing-Chung Hu

Rongsheng Yang

Hidetoshi Nozaki

Hongjun Li

Wei Dong Qian

Oray Orkun Cellek

Cunyu Yang

WeiDong Qian

Jizhang Shan

Dajiang Yang

Jin Li

Chih-Wei Hsiung

Zhiqiang Lin

Chia-Ying Liu

Hongli Yang

Manoj Bikumandla

Fei Wu

Zhenhong Fu

William Qian

Zhibin Xiong

Sasidhar Saladi

Nagaraja Satyadev

Ashish Shah

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.

Partial buried channel transfer device for image sensors

An example image sensor includes first, second, and third micro-lenses. The first micro-lens is in a first color pixel and has a first curvature and a first height. The second micro-lens is in a second color pixel and has a second curvature and a second height. The third micro-lens is in a third color pixel and has a third curvature and a third height. The first curvature is the same as both the second curvature and the third curvature and the first height is greater than the second height and the second height is greater than the third height, such that light absorption depths for the first, second, and third color pixels are the same.

Image sensor with color pixels having uniform light absorption depths

A method of forming microlenses for an image sensor having at least one large-area pixel and at least one small-area pixel is disclosed. The method includes forming a uniform layer of microlens material on a light incident side of the image sensor over the large-area pixel and over the small-area pixel. The method also includes forming the layer of microlens material into a first block disposed over the large-area pixel and into a second block disposed over the small-area pixel. A void is also formed in the second block to reduce a volume of microlens material included in the second block. The first and second blocks are then reflowed to form a respective first microlens and second microlens. The first microlens has substantially the same effective focal length as the second microlens.

Method of forming dual size microlenses for image sensors

An integrated circuit system includes a first device wafer bonded to a second device wafer at a bonding interface of dielectrics. Each wafer includes a plurality of dies, where each die includes a device, a metal stack, and a seal ring that is formed at an edge region of the die. Seal rings included in dies of the second device wafer each include a first conductive path provided with metal formed in a first opening that extends from a backside of the second device wafer, through the second device wafer, and through the bonding interface to the seal ring of a corresponding die in the first device wafer.

Die seal ring for integrated circuit system with stacked device wafers

Embodiments of the invention relate to a camera assembly including a rear-facing camera and a front-facing camera operatively coupled together (e.g., bonded, stacked on a common substrate). In some embodiments of the invention, a system having an array of frontside illuminated (FSI) imaging pixels is bonded to a system having an array of backside illuminated (BSI) imaging pixels, creating a camera assembly with a minimal size (e.g., a reduced thickness compared to prior art solutions). An FSI image sensor wafer may be used as a handle wafer for a BSI image sensor wafer when it is thinned, thereby decreasing the thickness of the overall camera module. According to other embodiments of the invention, two package dies, one a BSI image sensor, the other an FSI image sensor, are stacked on a common substrate such as a printed circuit board, and are operatively coupled together via redistribution layers.

Dual-facing camera assembly

Embodiments of an apparatus including a color filter arrangement formed on a substrate having a pixel array formed therein. The color filter arrangement includes a clear filter having a first clear hard mask layer and a second clear hard mask layer formed thereon, a first color filter having the first clear hard mask layer and the second hard mask layer formed thereon, a second color filter having the first clear hard mask layer formed thereon, and a third color filter having no clear hard mask layer formed thereon. Other embodiments are disclosed and claimed.

Color filter including clear pixel and hard mask

An image sensor pixel includes one or more photodiodes disposed in a semiconductor layer. Pixel circuitry is disposed in the semiconductor layer coupled to the one or more photodiodes. A passivation layer is disposed proximate to the semiconductor layer over the pixel circuitry and the one or more photodiodes. A contact etch stop layer is disposed over the passivation layer. One or more metal contacts are coupled to the pixel circuitry through the contact etch stop layer. One or more isolation regions are defined in the contact etch stop layer that isolate contact etch stop layer material through which the one or more metal contacts are coupled are coupled to the pixel circuitry from the one or more photodiodes.

Image sensor having metal contact coupled through a contact etch stop layer with an isolation region

Embodiments are disclosed of an apparatus comprising a color filter arrangement including a set of color filters. The set of color filters includes a pair of first color filters, each having first and second hard mask layers formed thereon, a second color filter having the first hard mask layer formed thereon, and a third color filter having no hard mask layer formed thereon. Other embodiments are disclosed and claimed.

Color filter patterning using hard mask

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.

Layers for increasing performance in image sensors

An image sensor includes a first pixel unit horizontally adjacent to a second pixel unit. Each pixel unit includes plurality of photodiodes and a shared floating diffusion region. A first pixel transistor region of the first pixel unit has a plurality of pixel transistors. A second pixel transistor region of the second pixel unit is horizontally adjacent to the first pixel transistor region and also has a plurality of pixel transistors. A transistor layout of the second pixel transistor region is a minor image of a transistor layout of the first pixel transistor region.

Image sensor with pixel units having mirrored transistor layout

Techniques and mechanisms for a pixel array to provide a level of conversion gain. In an embodiment, the pixel array includes conversion gain control circuitry to be selectively configured at different times for different operational modes, each mode for implementing a respective conversion gain. The conversion gain control circuitry selectively provides switched coupling of the pixel cell to&#x2014;and/or switched decoupling of the pixel cell from&#x2014;a supply voltage. In another embodiment, the conversion gain control circuitry selectively provides switched coupling of the pixel cell to&#x2014;and/or switched decoupling of the pixel cell from&#x2014;sample and hold circuitry.

Circuit structure for providing conversion gain of a pixel array

A pixel cell includes a photodiode disposed in an epitaxial layer in a first region of semiconductor material. A floating diffusion is disposed in a well region disposed in the epitaxial layer in the first region. A transfer transistor is disposed in the first region and coupled between the photodiode and the floating diffusion to selectively transfer image charge from the photodiode to the floating diffusion. A deep trench isolation (DTI) structure lined with a dielectric layer inside the DTI structure is disposed in the semiconductor material isolates the first region on one side of the DTI structure from a second region of the semiconductor material on an other side of the DTI structure. Doped semiconductor material inside the DTI structure is selectively coupled to a readout pulse voltage in response to the transfer transistor selectively transferring the image charge from the photodiode to the floating diffusion.

Image sensor pixel cell with switched deep trench isolation structure

A pixel cell includes a photodiode, a storage transistor, a transfer transistor and an output transistor disposed in a semiconductor substrate. The transfer transistor selectively transfers image charge accumulated in the photodiode from the photodiode to the storage transistor. The output transistor selectively transfers the image charge from the storage transistor to a readout node. A first isolation fence is disposed over the semiconductor substrate separating a transfer gate of the transfer transistor from a storage gate of the storage transistor. A second isolation fence is disposed over the semiconductor substrate separating the storage gate from an output gate of the output transistor. Thicknesses of the first and second isolation fences are substantially equal to spacing distances between the transfer gate and the storage gate, and between the storage gate and the output gate, respectively.

Image sensor pixel cell with global shutter having narrow spacing between gates

A pixel cell for use in a high dynamic range image sensor includes a photodiode disposed in semiconductor material to accumulate charge in response to light incident upon the photodiode. A transfer transistor is disposed in the semiconductor material and is coupled between a floating diffusion and the photodiode. A first amplifier transistor is disposed in the semiconductor material having a gate terminal coupled to the floating diffusion and a source terminal coupled to generate a first output signal of the pixel cell. A second amplifier transistor is disposed in the semiconductor material having a gate terminal coupled to the floating diffusion and a source terminal coupled to generate a second output signal of the pixel cell.

Growing community of inventors

San Jose, CA, United States of America

Hsin-Chih Tai