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Adri J. Mierop

Bio: Adri J. Mierop is an academic researcher from Delft University of Technology. The author has contributed to research in topics: Image sensor & Image noise. The author has an hindex of 4, co-authored 6 publications receiving 230 citations.

Papers
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Proceedings ArticleDOI
01 Dec 2006
TL;DR: In this paper, the 1/f noise of the Source Follower (SF) in pinned-photodiode CMOS pixels is characterized, and it is found that the noise in these pixels is actually due to a very limited number of traps and results in a Random Telegraph Signal (RTS).
Abstract: In this work, the 1/f noise of the Source Follower (SF) in pinned-photodiode CMOS pixels is characterized. It is found that the 1/f noise in these pixels is actually due to a very limited number of traps and results in a Random Telegraph Signal (RTS). It is pointed out how the correlated-double sampling (CDS) reacts on this RTS. The temperature dependency of the imager read noise revealed two mechanisms of RTS during CDS.

108 citations

Proceedings ArticleDOI
03 Apr 2012
TL;DR: By implementing a high-gain column-level amplifier and CMS technique together with an in-pixel buried-channel source follower (BSF) [6], the TRN level can be reduced even further.
Abstract: For low-light-level imaging, the performance of a CMOS image sensor (CIS) is usually limited by the temporal readout noise (TRN) generated from its analog readout circuit chain. Although a sub-electron TRN level can be achieved with a high-gain pixel-level amplifier, the pixel uniformity is highly impaired up to a few percent by its open-loop amplifier structure [1]. The TRN can be suppressed without this penalty by employing either a high-gain column-level amplifier [2] or a correlated multiple sampling (CMS) technique [3–5]. However, only 1-to-2 electron TRN level has been reported with the individual use of these approaches [2–5], and the low-frequency noise of the in-pixel source follower i.e. 1/fand RTS noise is a further limitation. Therefore, by implementing a high-gain column-level amplifier and CMS technique together with an in-pixel buried-channel source follower (BSF) [6], the TRN level can be reduced even further.

73 citations

Proceedings ArticleDOI
01 Feb 2008
TL;DR: Measurements show that compared to a regular imager with a standard nMOS transistor surface-mode source follower (SSF), the new pixel structure reduces dark random noise by more than 50% and improves output swing by almost 100%.
Abstract: This paper presents a CMOS image sensor with a pinned-photodiode 4T active-pixel design (APS) that uses a buried-channel source follower (BSF) as the in-pixel amplifier. A prototype of the image sensor has been fabricated in a 0.18mum CMOS process. Measurements show that compared to a regular imager with a standard nMOS transistor surface-mode source follower (SSF), the new pixel structure reduces dark random noise by more than 50% and improves output swing by almost 100%.

57 citations

Proceedings ArticleDOI
01 Nov 2010
TL;DR: In this article, the authors presented a CMOS image sensor with pinned-photodiode 5T active pixels which use an in-pixel buried channel source follower (BSF) with an optimized row selector (RS).
Abstract: This paper presents a CMOS image sensor (CIS) with pinned-photodiode 5T active pixels which use an in-pixel buried channel source follower (BSF) with an optimized row selector (RS). According to our previous work [1][2], using in-pixel BSFs with optimized RS can achieve significant pixel dark random noise reduction, i.e. 50% reduction, specially for random telegraph signal (RTS) noise, and an increase of the pixel output swing and dynamic range. With significant dark random noise reduction, in order to evaluate the performance for perspective space or medical imaging application, this proposed pixel structure using 0.18µm CMOS image sensor process is also further characterized under X-ray radiation. The results show that X-ray radiation induces additional acceptor-like interface traps which will increase dark random noise of the BSF pixels, to make BSF pixels less sensitive to radiation exposure, further optimization is necessary.

4 citations

Proceedings ArticleDOI
13 Oct 2011
TL;DR: In this article, an in-pixel buried channel source follower (BSF) with an optimized row selector (RS) was used to achieve significant pixel dark random noise reduction, i.e. 50% reduction, specially for random telegraph signal (RTS) noise.
Abstract: This paper presents a CMOS image sensor (CIS) with pinned-photodiode 5T active pixels which use an in-pixel buried channel source follower (BSF) with an optimized row selector (RS). According to our previous work [1][2], using in-pixel BSFs with optimized RS can achieve significant pixel dark random noise reduction, i.e. 50% reduction, specially for random telegraph signal (RTS) noise, and an increase of the pixel output swing and dynamic range. With significant dark random noise reduction, in order to evaluate the performance for perspective space or medical imaging application, this proposed pixel structure using 0.18μm CMOS image sensor process is also further characterized under X-ray radiation. The results show that although X-ray radiation induced additional acceptor-like interface traps will increase dark random noise, the BSF pixels are able to constrain the dark random noise increase after X-ray radiation.

3 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a probabilistic superposition of elementary Markov processes describing the trapping/detrapping events taking place in the cell tunnel oxide was proposed to explain the main features of the random telegraph noise threshold-voltage instability.
Abstract: This paper presents a new physics-based statistical model for random telegraph noise in Flash memories. From the probabilistic superposition of elementary Markov processes describing the trapping/detrapping events taking place in the cell tunnel oxide, the model can explain the main features of the random telegraph noise threshold-voltage instability. The results on the statistical distribution of the threshold-voltage difference between two subsequent read accesses show good agreement between measurements and model predictions, even considering the time drift of the distribution tails. Moreover, the model gives a detailed spectroscopic analysis of the oxide defects responsible for the random telegraph noise, allowing a spatial and energetic localization of the traps involved in the threshold-voltage instability process.

129 citations

Journal ArticleDOI
TL;DR: In this paper, a CMOS single-photon avalanche diode (SPAD)-based quarter video graphics array image sensor with 8- $\mu \text{m}$ pixel pitch and 26.8% fill factor was presented.
Abstract: A CMOS single-photon avalanche diode (SPAD)-based quarter video graphics array image sensor with 8- $\mu \text{m}$ pixel pitch and 26.8% fill factor (FF) is presented. The combination of analog pixel electronics and scalable shared-well SPAD devices facilitates high-resolution, high-FF SPAD imaging arrays exhibiting photon shot-noise-limited statistics. The SPAD has 47 counts/s dark count rate at 1.5 V excess bias (EB), 39.5% photon detection probability (PDP) at 480 nm, and a minimum of 1.1 ns dead time at 1 V EB. Analog single-photon counting imaging is demonstrated with maximum 14.2-mV/SPAD event sensitivity and 0.06e− minimum equivalent read noise. Binary quanta image sensor (QIS) 16-kframes/s real-time oversampling is shown, verifying single-photon QIS theory with $4.6\times $ overexposure latitude and 0.168e− read noise.

108 citations

Journal ArticleDOI
Eric R. Fossum1, Jiaju Ma1, Saleh Masoodian1, Leo Anzagira1, Rachel Zizza1 
10 Aug 2016-Sensors
TL;DR: The Quanta Image Sensor (QIS) concept and its imaging characteristics are reviewed, which represents a possible major paradigm shift in image capture.
Abstract: The Quanta Image Sensor (QIS) was conceived when contemplating shrinking pixel sizes and storage capacities, and the steady increase in digital processing power. In the single-bit QIS, the output of each field is a binary bit plane, where each bit represents the presence or absence of at least one photoelectron in a photodetector. A series of bit planes is generated through high-speed readout, and a kernel or “cubicle” of bits (x, y, t) is used to create a single output image pixel. The size of the cubicle can be adjusted post-acquisition to optimize image quality. The specialized sub-diffraction-limit photodetectors in the QIS are referred to as “jots” and a QIS may have a gigajot or more, read out at 1000 fps, for a data rate exceeding 1 Tb/s. Basically, we are trying to count photons as they arrive at the sensor. This paper reviews the QIS concept and its imaging characteristics. Recent progress towards realizing the QIS for commercial and scientific purposes is discussed. This includes implementation of a pump-gate jot device in a 65 nm CIS BSI process yielding read noise as low as 0.22 e− r.m.s. and conversion gain as high as 420 µV/e−, power efficient readout electronics, currently as low as 0.4 pJ/b in the same process, creating high dynamic range images from jot data, and understanding the imaging characteristics of single-bit and multi-bit QIS devices. The QIS represents a possible major paradigm shift in image capture.

85 citations

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the effect of different types of ionizing radiation on PPD CMOS Image Sensors and proposed mechanisms at the origin of these degradations.
Abstract: Several Pinned Photodiode (PPD) CMOS Image Sensors (CIS) are designed, manufactured, characterized and exposed biased to ionizing radiation up to 10 kGy(SiO2 ). In addition to the usually reported dark current increase and quantum efficiency drop at short wavelengths, several original radiation effects are shown: an increase of the pinning voltage, a decrease of the buried photodiode full well capacity, a large change in charge transfer efficiency, the creation of a large number of Total Ionizing Dose (TID) induced Dark Current Random Telegraph Signal (DC-RTS) centers active in the photodiode (even when the Transfer Gate (TG) is accumulated) and the complete depletion of the Pre-Metal Dielectric (PMD) interface at the highest TID leading to a large dark current and the loss of control of the TG on the dark current. The proposed mechanisms at the origin of these degradations are discussed. It is also demonstrated that biasing (i.e., operating) the PPD CIS during irradiation does not enhance the degradations compared to sensors grounded during irradiation.

78 citations

Proceedings ArticleDOI
03 Apr 2012
TL;DR: By implementing a high-gain column-level amplifier and CMS technique together with an in-pixel buried-channel source follower (BSF) [6], the TRN level can be reduced even further.
Abstract: For low-light-level imaging, the performance of a CMOS image sensor (CIS) is usually limited by the temporal readout noise (TRN) generated from its analog readout circuit chain. Although a sub-electron TRN level can be achieved with a high-gain pixel-level amplifier, the pixel uniformity is highly impaired up to a few percent by its open-loop amplifier structure [1]. The TRN can be suppressed without this penalty by employing either a high-gain column-level amplifier [2] or a correlated multiple sampling (CMS) technique [3–5]. However, only 1-to-2 electron TRN level has been reported with the individual use of these approaches [2–5], and the low-frequency noise of the in-pixel source follower i.e. 1/fand RTS noise is a further limitation. Therefore, by implementing a high-gain column-level amplifier and CMS technique together with an in-pixel buried-channel source follower (BSF) [6], the TRN level can be reduced even further.

73 citations