Micron Technology Incorporated

Aptina Imaging Corporation

Semiconductor Components Industries, LLC

Sungkwon C Hong

Inna V Patrick

Alex Krymski

Gordon M Grivna

David T Price

Rick Carlton Jerome

Howard E Rhodes

Gennadiy A Agranov

Richard A Mauritzson

Jeffrey A McKee

Ji Soo Lee

Kalairaja Chinnaveerappan

Canaan S Hong

Sungkuk Hong

An image sensor structure includes a region of semiconductor material having a first major surface and a second major surface. A pixel structure is within the region of semiconductor material and includes a plurality of doped regions and a plurality of conductive structures. A metal-filled trench structure extends from the first major surface to the second major surface. A first contact structure is electrically connected to a first surface of the conductive trench structure, and a second contact structure electrically connected to a second surface of the conductive trench structure. In one embodiment, the second major surface is configured to receive incident light.

Semiconductor image sensor structure having metal-filled trench contact

An imaging pixel may be provided with a photodiode and a floating diffusion region. The pixel may include at least one storage capacitor that can store charge from the floating diffusion region. The at least one storage capacitor may provide global shutter functionality for the pixel. Multiple storage capacitors may be provided for correlated double sampling (CDS) techniques and high dynamic range (HDR) images. The imaging pixel may have an upper substrate layer and a lower substrate layer. The photodiode may be formed in the upper substrate layer, and the storage capacitors may be formed in the lower substrate layer. A interconnect layer may couple pixel circuitry in the upper substrate layer to pixel circuitry in the lower substrate layer.

Pixels with a global shutter and high dynamic range

In one embodiment, a method for forming a backside illuminated image sensor includes providing a region of semiconductor material having a first major surface and a second major surface configured to receive incident light. A pixel structure is formed within the region of semiconductor material adjacent the first major surface. Thereafter, a trench structure comprising a metal material is formed extending through the region of semiconductor material. A first surface of the trench structure is adjacent the first major surface of the region of semiconductor material and a second surface adjoining the second major surface of the region of semiconductor material. A first contact structure is electrically connected to one surface of the conductive trench structure and a second contact structure is electrically connected to an opposing second surface.

Method for forming a semiconductor image sensor device

A pixel cell has controlled photosensor anti-blooming leakage by having dual pinned voltage regions, one of which is used to set the anti-blooming characteristics of the photosensor. Additional exemplary embodiments also employ an anti-blooming transistor in conjunction with the dual pinned photosensor. Other exemplary embodiments provide a pixel with two pinned voltage regions and two anti-blooming transistors. Methods of fabricating the exemplary pixel cells are also disclosed.

Wide dynamic range sensor having a pinned diode with multiple pinned voltages

A barrier for isolating the dark correction pixels from spurious charges within an image sensor. The barrier comprises a charge absorbing region in a substrate electrically connected to a voltage source terminal. The charge absorbing region completely surrounds the dark correction region of a pixel array. The charge absorbing region absorbs carriers generated by lateral diffusion, near-infrared and infrared light reflected from the bottom of the silicon substrate, and other sources. This absorbing region prevents carriers from being absorbed into the dark correction pixel cells and causing image correction distorting effects.

Method and apparatus for shielding correction pixels from spurious charges in an imager

Methods for operating a pixel cell include efficient transferring of photo-charges using multiple pulses to a transistor transfer gate during a charge integration period for an associated photosensor. The pixel cell can be operated with efficient transfer characteristics in either normal or high dynamic range (HDR) mode. The high dynamic range can be realized by either operating an optional HDR transistor or by fluctuating the voltage applied to a reset gate.

Method for operating a pixel cell using multiple pulses to a transistor transfer gate

A pixel cell in which a capacitance is coupled between a storage node and a row select transistor and another capacitance is coupled between a storage node and a voltage supply or ground source potential to boost a reset voltage.

Imager pixel with capacitance circuit for boosting reset voltage

Pixel cells are provided which employ a gate capacitor associated with the floating diffusion node to selectively increase the storage capacity of the floating diffusion node. The gate capacitor can be formed at the same time as the same process steps used to form other gates of the pixel cells. The inherent capacity of the storage node alone may be sufficient under low light conditions. Higher light conditions may result in selective activation of the gate capacitor, thus increasing the capacity of the storage node with the additional capacity provided by the gate capacitor. The invention produces high dynamic range and high output signal without charge sharing or lag output signal. Methods of forming such pixel cells can be applied in CMOS and CCD imaging devices, image pixel arrays in CMOS and CCD imaging devices, and CMOS and CCD imager systems.

Image sensor with floating diffusion gate capacitor

The exemplary embodiments provide an imager with dual conversion gain charge storage and thus, improved dynamic range. A dual conversion gain element (e.g., Schottky diode) is coupled between a floating diffusion region and a respective capacitor. The dual conversion gain element switches in the capacitance of the capacitor, in response to charge stored at the floating diffusion region, to change the conversion gain of the floating diffusion region from a first conversion gain to a second conversion gain. In an additional aspect, the exemplary embodiments provide an ohmic contact between the gate of a source follower transistor and the floating diffusion region which assists in the readout of the dual conversion gain output signal of a pixel.

Dual conversion gain pixel using Schottky and ohmic contacts to the floating diffusion region and methods of fabrication and operation

A method of fabricating a pixel cell having a shutter gate structure. First and second charge barriers are respectively created between a photodiode and a first charge storage region and between the first storage region and a floating diffusion region. A global shutter gate is formed to control the charge barrier and transfer charges from the photodiode to the first charge storage region by effectively lowering the first charge barrier. A transfer transistor acts to transfer charges from the first storage region to the floating diffusion region by reducing the second charge barrier.

Method of fabricating a storage gate pixel design

A pixel cell comprises a photo-conversion device for generating charge and a gate controlled charge storage region for storing photo-generated charge under control of a control gate. The charge storage region can be a single CCD stage having a buried channel to obtain efficient charge transfer and low charge loss. The charge storage region is adjacent to a gate of a transistor. The transistor gate is adjacent to the photo-conversion device and, in conjunction with the control gate, transfers photo-generated charge from the photo-conversion device to the charge storage region.

Imaging with gate controlled charge storage

A device, as in an integrated circuit, includes diverse components such as transistors and capacitors. After conductive layers for all types of components are produced, a silicide layer is provided over conductive layers, reducing resistance. The device can be an imager in which pixels in an array includes a capacitor and readout circuitry with NMOS transistors. Periphery circuitry around the array can include PMOS transistors. Because the silicide layer is formed after the conductive layers, it is not exposed to high temperatures and, therefore, migration and cross-contamination of dopants is reduced.

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Boise, ID, United States of America

Sungkwon C Hong