Effects of Offset Pixel Aperture Width on the Performances of Monochrome CMOS Image Sensors for Depth Extraction

This paper presents the effects of offset pixel aperture width on the performance of monochrome (MONO) CMOS image sensors (CISs) for a three-dimensional image sensor. Using a technique to integrate the offset pixel aperture (OPA) inside each pixel, the depth information can be acquired using a disparity from OPA patterns. The OPA is classified into two pattern types: Left-offset pixel aperture (LOPA) and right-offset pixel aperture (ROPA). These OPAs are divided into odd and even rows and integrated in a pixel array. To analyze the correlation between the OPA width and the sensor characteristics, experiments were conducted by configuring the test elements group (TEG) regions. The OPA width of the TEG region for the measurement varied in the range of 0.3–0.5 μm. As the aperture width decreased, the disparity of the image increased, while the sensitivity decreased. It is possible to acquire depth information by the disparity obtained from the proposed MONO CIS using the OPA technique without an external light source. Therefore, the proposed MONO CIS with OPA could easily be applied to miniaturized devices. The proposed MONO CIS was designed and manufactured using the 0.11 μm CIS process.

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1/f Noise Modelling and Characterization for CMOS Quanta Image Sensors

Sensors ◽

10.3390/s19245459 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5459

Author(s):

Wei Deng ◽

Eric R. Fossum

Keyword(s):

Analog Circuits ◽

Image Sensor ◽

Image Sensors ◽

Correlated Double Sampling ◽

Cmos Image Sensors ◽

Source Follower ◽

Cmos Analog Circuits ◽

Different Origins ◽

Noise Models ◽

Fitting Model

This work fits the measured in-pixel source-follower noise in a CMOS Quanta Image Sensor (QIS) prototype chip using physics-based 1/f noise models, rather than the widely-used fitting model for analog designers. This paper discusses the different origins of 1/f noise in QIS devices and includes correlated double sampling (CDS). The modelling results based on the Hooge mobility fluctuation, which uses one adjustable parameter, match the experimental measurements, including the variation in noise from room temperature to –70 °C. This work provides useful information for the implementation of QIS in scientific applications and suggests that even lower read noise is attainable by further cooling and may be applicable to other CMOS analog circuits and CMOS image sensors.

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Proximity Gettering Design of Hydrocarbon–Molecular–Ion–Implanted Silicon Wafers Using Dark Current Spectroscopy for CMOS Image Sensors

Sensors ◽

10.3390/s19092073 ◽

2019 ◽

Vol 19 (9) ◽

pp. 2073 ◽

Cited By ~ 4

Author(s):

Kazunari Kurita ◽

Takeshi Kadono ◽

Satoshi Shigematsu ◽

Ryo Hirose ◽

Ryosuke Okuyama ◽

...

Keyword(s):

Dark Current ◽

Image Sensor ◽

Image Sensors ◽

Silicon Wafers ◽

Device Fabrication ◽

Oxide Semiconductor ◽

Device Performance ◽

Molecular Ion ◽

Cmos Image Sensors ◽

Ion Implanted

We developed silicon epitaxial wafers with high gettering capability by using hydrocarbon–molecular–ion implantation. These wafers also have the effect of hydrogen passivation on process-induced defects and a barrier to out-diffusion of oxygen of the Czochralski silicon (CZ) substrate bulk during Complementary metal-oxide-semiconductor (CMOS) device fabrication processes. We evaluated the electrical device performance of CMOS image sensor fabricated on this type of wafer by using dark current spectroscopy. We found fewer white spot defects compared with those of intrinsic gettering (IG) silicon wafers. We believe that these hydrocarbon–molecular–ion–implanted silicon epitaxial wafers will improve the device performance of CMOS image sensors.

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Super Field-of-View Lensless Camera by Coded Image Sensors

Sensors ◽

10.3390/s19061329 ◽

2019 ◽

Vol 19 (6) ◽

pp. 1329 ◽

Cited By ~ 3

Author(s):

Tomoya Nakamura ◽

Keiichiro Kagawa ◽

Shiho Torashima ◽

Masahiro Yamaguchi

Keyword(s):

Imaging System ◽

Complementary Metal Oxide Semiconductor ◽

Image Sensor ◽

Image Sensors ◽

Computational Imaging ◽

Field Of View ◽

Oxide Semiconductor ◽

Back Side ◽

Cmos Image Sensors ◽

Rich Information

A lensless camera is an ultra-thin computational-imaging system. Existing lensless cameras are based on the axial arrangement of an image sensor and a coding mask, and therefore, the back side of the image sensor cannot be captured. In this paper, we propose a lensless camera with a novel design that can capture the front and back sides simultaneously. The proposed camera is composed of multiple coded image sensors, which are complementary-metal-oxide-semiconductor (CMOS) image sensors in which air holes are randomly made at some pixels by drilling processing. When the sensors are placed facing each other, the object-side sensor works as a coding mask and the other works as a sparsified image sensor. The captured image is a sparse coded image, which can be decoded computationally by using compressive sensing-based image reconstruction. We verified the feasibility of the proposed lensless camera by simulations and experiments. The proposed thin lensless camera realized super-field-of-view imaging without lenses or coding masks and therefore can be used for rich information sensing in confined spaces. This work also suggests a new direction in the design of CMOS image sensors in the era of computational imaging.

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A 4-tap global shutter pixel with enhanced IR sensitivity for VGA time-of-flight CMOS image sensors

Electronic Imaging ◽

10.2352/issn.2470-1173.2020.7.iss-103 ◽

2020 ◽

Vol 2020 (7) ◽

pp. 103-1-103-6

Author(s):

Taesub Jung ◽

Yonghun Kwon ◽

Sungyoung Seo ◽

Min-Sun Keel ◽

Changkeun Lee ◽

...

Keyword(s):

Time Of Flight ◽

Light Sensitivity ◽

Image Sensor ◽

Image Sensors ◽

Double Sampling ◽

Back Side ◽

Long Distance ◽

Correlated Double Sampling ◽

Cmos Image Sensors ◽

Side Illumination

An indirect time-of-flight (ToF) CMOS image sensor has been designed with 4-tap 7 μm global shutter pixel in back-side illumination process. 15000 e- of high full-well capacity (FWC) per a tap of 3.5 μm pitch and 3.6 e- of read-noise has been realized by employing true correlated double sampling (CDS) structure with storage gates (SGs). Noble characteristics such as 86 % of demodulation contrast (DC) at 100MHz operation, 37 % of higher quantum efficiency (QE) and lower parasitic light sensitivity (PLS) at 940 nm have been achieved. As a result, the proposed ToF sensor shows depth noise less than 0.3 % with 940 nm illuminator in even long distance.

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(Invited) Development of Novel Three-Dimensional Structuring of Integrated Circuits by Using Low Temperature Direct Bonding for CMOS Image Sensors

ECS Transactions ◽

10.1149/06106.0087ecst ◽

2014 ◽

Vol 61 (6) ◽

pp. 87-90 ◽

Cited By ~ 1

Author(s):

M. Goto ◽

K. Hagiwara ◽

Y. Iguchi ◽

H. Ohtake ◽

T. Saraya ◽

...

Keyword(s):

Low Temperature ◽

Integrated Circuits ◽

Three Dimensional ◽

Image Sensors ◽

Cmos Image Sensors

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A CMOS voltage-mode image sensing system

10.32920/ryerson.14645022.v1 ◽

2021 ◽

Author(s):

Jun Long Zhang

Keyword(s):

Cmos Image Sensor ◽

Cmos Technology ◽

Image Sensor ◽

Electrical Signal ◽

Image Sensors ◽

Analog To Digital ◽

Light Sensing ◽

Image Sensing ◽

Cmos Image Sensors ◽

Pixel Sensors

A CMOS image sensor consists of a light sensing region that converts photonic energy to an electrical signal and a peripheral circuitry that performs signal conditioning and post-processing. This project investgates the principle and design of CMOS active image sensors. The basic concepts and principle of CMOS image sensors are investigated. The advantages of CMOS image sensors over charge-coupled device (CCD) image sensors are presented. Both passive pixel sensors (PPS) and acive pixel sensors (APS) are examined in detail. The noise of CMOS image sensors is investigated and correlated double sampling (CDS) techniques are examined. The design of APS arrays, CDS circuits and 8-bit analog to-digital converters in TSMC-0.18μm 1.8V CMOS technology is presented. The simulation results and layout of the designed CMOS image sensor are presented.

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