Academic literature on the topic 'Monolithic active pixel sensor (MAPS)'

Abstract HV-MAPS are a novel type of CMOS depleted active pixel sensors for ionizing particles, implemented in standard CMOS processes, that have been proposed in several future particle physics experiments for particle tracking. In depleted monolithic sensors, the sensor element is the n-well/p-substrate diode. The sensor matrix and the readout are integrated in one single piece of silicon and the electronics is embedded in shallow wells inside deep n-wells, isolated from the substrate. High voltage biasing increases the depth of the depletion region, improving sensor properties as signal amplitude, charge collection speed and radiation tolerance. ATLASPix3 is the first full reticle size high voltage Monolithic Active Pixel CMOS sensor, designed to meet the specifications of the outer layers of the ATLAS inner tracker (ITk). Its thin design, the excellent position resolution, high readout rate and high radiation tolerance make ATLASPix3 an ideal candidate for large-area tracking detector R&D of future collider experiments such as the Circular Electron Positron Collider (CEPC) silicon tracker.

Intensity-modulated radiotherapy is a widely used technique for accurately targeting cancerous tumours in difficult locations using dynamically shaped beams. This is ideally accompanied by real-time independent verification. Monolithic active pixel sensors are a viable candidate for providing upstream beam monitoring during treatment. We have already demonstrated that a Monolithic Active Pixel Sensor (MAPS)-based system can fulfill all clinical requirements except for the minimum required size. Here, we report the performance of a large-scale demonstrator system consisting of a matrix of 2 × 2 sensors, which is large enough to cover almost all radiotherapy treatment fields when affixed to the shadow tray of the LINAC head. When building a matrix structure, a small dead area is inevitable. Here, we report that with a newly developed position algorithm, leaf positions can be reconstructed over the entire range with a position resolution of below ∼200 μm in the centre of the sensor, which worsens to just below 300 μm in the middle of the gap between two sensors. A leaf position resolution below 300 μm results in a dose error below 2%, which is good enough for clinical deployment.

Abstract Monolithic active pixel sensors (MAPS) are now well established as a technology for tracking charged particles, especially when low material budget is desirable. For such applications, sensors focus on spatial resolution and pixels with digital output or modest charge measurement ability are well suited. Within the European Union STRONG-2020 project, which focuses on experiments using hadrons, the TIIMM (Tracking and Ions Identifications with Minimal Material budget) joint research activity intends to expand granular MAPS capacity to energy-loss (ΔE) measurement for ion species identification. The TIIMM prototypes are developed in the Tower Jazz 180 nm CMOS image sensor (CIS) process. The Time-Over-Threshold (ToT) method is applied to the sensor for the energy-loss measurement. The main design details and the preliminary test results from laboratory measurements of the initial TIIMM prototype are presented in this work.

Abstract The SpacePix2 monolithic active pixel sensor (MAPS) is a novel ASIC for space radiation monitoring designed in a 180 nm SOI CMOS technology. The active sensor area is 3.84 × 3.84 mm2, pixel matrix is arranged as a 64 × 64 array with 60 µm pitch. The pixel front-end amplifier signal range is 2–80 ke−, extended up to 30 Me− using a backside channel. Diodes integrated in the handle wafer in each pixel are biased at −150 V. Impinging particle generates a charge pulse converted to voltage pulse by charge sensitive amplifier (CSA). Maximum voltage memorized by the peak detector hold (PDH) circuit is digitized using on-chip 10-bit asynchronous column SAR ADCs. Two readout interfaces are available, 400 MHz LVDS and 50 MHz SPI. Total power consumption is 43 mA from a 1.8 V power supply. The ASIC has been tested in space in low Earth orbit (LEO) and sample data are shown.

The SiD detector concept capitalizes on high granularity in its tracker and calorimeter to achieve the momentum resolution and particle flow calorimetry physics goals in a compact design. The collaboration has had a long interest in the potential for improved granularity in both the tracker and ECal with an application of monolithic active pixel sensors (MAPS) and a study of MAPS in the SiD ECal was described in the ILC TDR. Work is progressing on the MAPS application in an upgraded SiD design with a prototyping design effort for a common SiD tracker/ECal design based on stitched reticules to achieve 10 × 10 cm2 sensors with 25 × 100 micron2 pixels. Application of large area MAPS in these systems would limit delicate and expensive bump-bonding, provide possibilities for better timing, and should be significantly cheaper than the TDR concept due to being a more conventional CMOS foundry process. The small pixels significantly improve shower separation. Recent simulation studies confirm previous performance projections, indicating electromagnetic energy resolution based on digital hit cluster counting provides better performance than the SiD TDR analog design based on 13 mm2 pixels. Furthermore, the two shower separation is excellent down to the millimeter scale. Geant4 simulation results demonstrate these expectations.

ABSTRACTA model of a High Voltage CMOS (HV-CMOS) Monolithic Active Pixel Sensor (MAPS) has been modelled using Technology Computer Aided Design (TCAD). The model has incorporated both the active region and the on-pixel readout circuits which were comprised of a source follower amplifier and an integrated charge amplifier. The simulation has examined the electrical characteristics and response output of a HV-CMOS MAPS sensor using typical dimensions, levels of doping in the structural layers and bias conditions for this sensor. The performance of two alternate designs of amplifier have been examined as a function of the operating parameters. The response of the sensor to the incidence of Minimum Ionizing Particles (MIPs) at different energies has been included in the model.

Abstract A Monolithic Active Pixel Sensor (MAPS) is currently being designed in a new 130 nm high-resistivity (>1 kΩ·cm) CMOS process for full image beam monitoring in the carbon-ion therapeutic facility. The charge sensing node collects the charge deposited by the carbon ions that pass through the MAPS. A 3-dimensional TCAD model of the pixel has been established to study the carbon-ion induced process in the MAPS. This paper will discuss the thickness of the depletion layer, the charge collection efficiency, the charge collection time, and the characteristics of NMOS devices with different bias voltages and carbon-ion hitting locations.

Abstract Recent advancements in Monolithic Active Pixel Sensors (MAPS) demonstrated the ability to operate in high radiation environments of up to multiple kGy’s, which increased their appeal as sensors for high-energy physics detectors. The most recent example in such application is the new ALICE inner tracking system, entirely instrumented with CMOS MAPS, that covers an area of about 10 m2. However, the full potential of such devices has not yet been fully exploited, especially in respect of the size of the active area, power consumption, and timing capabilities. The ARCADIA project is developing Fully Depleted (FD) MAPS with an innovative sensor design, that uses a proprietary processing of the backside to improve the charge collection efficiency and timing over a wide range of operational and environmental conditions. The innovative sensor design targets very low power consumption, of the order of 20 mW cm−2 at 100 MHz cm−2 hit flux, to enable air-cooled operations of the sensors. Another key design parameter is the ability to further reduce the power regime of the sensor, down to 5 mW cm−2 or better, for low hit rates like e.g. expected in space experiments. In this contribution, we present a comparison between the detector characteristics predicted with Technology Computer Aided Design (TCAD) simulations and the ones measured experimentally. The comparison focuses on the current-voltage (IV) and capacitance-voltage (CV) characteristics, as well as noise estimated from in-pixel capacitances of passive/active pixel matrices. In view of the targeted applications of this technology, an emphasis is set on the modeling of X-ray induced radiation damage at the Si-SiO2 interface and the impact on the in-pixel sensor capacitance. The so-called new Perugia model has been used in the simulations to predict the sensor performance after total ionizing doses of up to 10 Mrad.

Abstract With Inner Tracking System v3 (ITS3), the ALICE experiment is pursuing a wafer-scale Monolithic Active Pixel Sensor (MAPS). The chip is being developed in TPSCo 65 nm ISC technology which is under study in the framework of CERN EP R&D on monolithic sensors for High Energy Physics (HEP) applications. This contribution presents designs and measurement results of building blocks needed for this chip, in particular bandgap references and temperature sensors. In addition, simulation results of the design of Low Drop-out Regulator (LDO) to be submitted for the next prototyping run will be discussed.

This study presents a real-time monitoring technique for radioactive substances that meets safety management needs. We studied the accumulation characteristics of radiation response signals of monolithic active pixel sensors (MAPSs) based on their response and discrimination ability to gamma (γ) photon or neutron radiation. The radiation status of the radioactive substances was determined by monitoring the accumulation data of radiation responses. As per the results, Am-Be and 252Cf radiation response signals are primarily concentrated in the range of 0–70 pixels. Response signals of 60Co and 137Cs γ-ray were concentrated in two regions; there was a peak in the region with a pixel value of less than 50, and a plateau in the region with a pixel value of more than 75. Therefore, the results are able to discriminate between spectra. Furthermore, we designed a radioactivity monitoring system that is able to examine multiple radioactive materials. Its working principle is that a change in the accumulation of radioactivity monitoring data indicates a radiation change during the last accumulation cycle. This study provides vital technical support for the long-term supervision of radioactive substances.

ALICE (A Large Ion Collider Experiment) is a general-purpose, heavy-ion detector at the CERN LHC designed to study the physics of strongly interacting matter, and in particular the properties of the Quark-Gluon Plasma (QGP), using Pb-Pb collisions at unprecedented energy densities. During the first three years of operation, it has demonstrated very good capabilities for measurements at high energy Pb-Pb collisions. But there are certain measurements like high precision measurements of rare probes over a wide range of momenta, which would require high statistics and are not satisfactory or even possible with the current experimental setup. These measurements would help to achieve the long term physics goals of ALICE and would go a long way forward in understanding and characterizing the Quark Gluon Plasma (QGP). To enhance its physics capabilities, ALICE has formulated an upgrade of its detectors, motivated by an upgrade of the LHC during the LHC Long Shutdown 2 (2018-2020). The LHC upgrade features which primarily motivated the ALICE upgrade programme are, in particular, Pb-Pb collisions with a high interaction rate of up to 50 kHz corresponding to an instantaneous luminosity, L = 6 × 1027cm−2s−1 and, the installation of a narrower beam pipe. Accordingly, ALICE would require detector upgrades to cope with the upgrade scenario. These upgrades should help to improve tracking and vertexing capabilities, radiation hardness and allow readout of all interactions to accumulate enough statistics for the upgrade physics programme. The objective is to accumulate 10 nb−1 of Pb–Pb collisions, recording about 1011 interactions. Within this upgrade strategy, the Inner Tracking System (ITS) upgrade forms an important cornerstone, providing improved vertexing and readout capabilities. The new ITS will have a barrel geometry consisting of seven layers of Monolithic Active Pixel Sensors (MAPS) with high granularity which would cater to the material budget, readout and radiation hardness requirements for the upgrade. The geometry is optimized for high efficiency, both in standalone tracking and ITS-TPC combined tracking. TowerJazz 0.18 μm technology is selected for designing the pixels for ITS upgrade. This technology provides attractive features like the option to implement a deep pwell allowing the implementation of a full CMOS process in the pixel. The ongoing research and development on these pixels investigates different design strategies and would converge towards the final design of the detector by the end of 2014. Several prototypes have been designed to investigate and validate the different design strategies and the different components of the pixel detector using this technology. The work presented in this thesis can be categorized in two parts. The first part concerns the results of characterization of some of the pixel prototype circuits developed for the ITS upgrade, in particular MIMOSA32, MIMOSA32Ter and Explorer-1. The second part discusses the detector performance studies of the upgraded ITS. MIMOSA32 and MIMOSA32Ter were one of the first prototypes designed with the TowerJazz technology in the upgrade programme. The motivation was to validate the technology. This thesis includes the results of tests and characterization of pixel structures of these prototypes and qualifies the technology in terms of charge collection and radiation tolerance and the usage of the deep p-well structure. This provides a starting point for future prototypes where the deep p-well could be implemented in a full CMOS process, thus allowing in-pixel sophisticated signal processing circuits. The Explorer prototypes are developed at CERN with the main motivation towards developing a detector with low power density, lower than the maximum permissible limits for the upgrade programme. This would provide a margin to reduce the material budget of the detection layers, improving the detector performance. The Explorer prototypes are designed to study the ratio of the collected charge to the input capacitance (Q/C), in particular, its dependence on the size of the collection diode and its distance to the adjacent p-well of the input transistors. The Explorer prototypes allows the application of a back-bias voltage which has an effect on the signal collection properties. In a pixel detector, improvement of the Q/C ratio enhances the signal amplitude at the collection node of the pixel circuit which is connected to the analog frontend. This would help in optimizing the analog frontend to improve the signal to noise ratio of the detector, which has a direct consequence in minimizing the power consumption of the detector. This thesis includes the test and characterization of Explorer-1 prototype circuits with different starting materials. The results show that Q/C improves with higher back bias voltage and increased spacing between the collection electrode and the adjacent p-well. With these results, the future prototypes of Explorer could concentrate on Optimizing the size of the input transistors to study its effects on the Random Telegraph Signal noise. In parallel, optimization of the signal processing circuits would also be carried out in other prototypes. The second part of the thesis studies the performance of a baseline configuration of the upgraded detector in terms of impact parameter resolution, momentum resolution and tracking efficiency both in standalone tracking mode and ITS-TPC combined tracking. The performance is compared with the current ITS to study the improvements in the upgraded ITS. The performance is affected by the radial position and material budget of the layers and the detector intrinsic resolution. The detector specifications in this regard are still evolving specially for the Outer Barrel (the outermost four layers). The studies show the effects of variation of the specifications in terms of material budget and intrinsic resolution on the detector performance. This would help to finalize the detector specifications for an optimized detector performance. The thesis also concludes that a reduction in the beam pipe radius (lower than the baseline upgrade scenario) would not affect detector performance but may facilitate the installation of the Inner Barrel. Redundancy studies show that the presence of a dead layer can degrade the detector performance significantly. This defines a key requirement of easy and rapid accessibility to the detector in the design of the upgraded ITS. The ITS upgrade timeline foresees the finalization of the final pixel architecture in late 2014. Mass production of the final circuit is planned for 2015. The construction of the detector modules, tests, assembling and pre-commissioning will be carried out throughout 2016-2017 followed by the installation of the detector in the ALICE cavern in 2018.

Monolithic Active Pixel Sensors (MAPS) are good candidates to be used in High Energy Physics (HEP) experiments for charged particle detection. In the HEP applications, MAPS chips are placed very close to the interaction point and are directly exposed to harsh environmental radiation. This thesis focuses on the study and improvement of the MAPS radiation hardness. The main radiation effects and the research progress of MAPS are studied firstly. During the study, the SRAM IP cores built in MAPS are found limiting the radiation hardness of the whole MAPS chips. Consequently, in order to improve the radiation hardness of MAPS, three radiation hard memories are designed and evaluated for the HEP experiments. In order to replace the SRAM IP cores, a radiation hard SRAM is developed on a very limited area. For smaller feature size processes, in which the single event upset (SEU) effects get significant, a radiation hard SRAM with enhanced SEU tolerance is implemented by an error detection and correction algorithm and a bit-interleaving storage. In order to obtain higher radiation tolerance and higher circuitry density, a dual-port memory with an original 2-transistor cell is developed and evaluated for future MAPS chips. Finally, the radiation hardness of the MAPS chips using new available processes is studied, and the future works are prospected.

L'expérience CBM (Compressed Baryonic Matter) a pour objet d'explorer le diagramme des phases de la matière nucléaire dans la région des hautes densités baryoniques au moyen de collisions d'ions lourds à des énergies de faisceau comprises entre 10 et 40 AGeV. Dans le but d'étudier le charme ouvert (D0 et D+) avec CBM, un détecteur de vertex (MVD) présentant à la fois un faible budget de matière, une excellente résolution spatiale et une bonne tolérance aux radiations est requis. Cette étude vise à déterminer dans quelle mesure un MVD constitué de capteurs CMOS (MAPS) peut garantir de telles performances. Dans cette optique le cahier des charges du MVD a été établi. Les mécanismes de dégradation par irradiation des MAPS ont été étudiés pour en améliorer la tolérance d'un ordre de grandeur. Les résultats de ces études ont permis de réaliser des simulations avec GEANT, et de démontrer la faisabilité du programme de physique portant sur le charme ouvert avec un tel concept de détecteur
The Compressed Baryonic Matter experiment (CBM) will investigate heavy ion collisions at beam energies between 10 and 40 AGeV in order to explore the nuclear matter phase diagram in the high baryon density region. For a first time, open charm mesons (D0 and D±) will be used as probe for the nuclear fireball. Reconstructing them requires a very thin (few 0. 1 % X0 per layer) micro vertex detector (MVD) with pixel sensors featuring excellent spatial resolution (few µm) and substantial radiation hardness. This work studies whether (and how) an MVD based on the novel Monolithic Active Pixel Sensors (MAPS) can the reach the performance needed. For this purpose, the precise requirements on the MVD in terms of material budget, cooling, time resolution and radiation hardness were estimated. Extensive R&D studies on MAPS allowed establishing their performances in particular in the field of radiation tolerance and to improve this tolerance by one order of magnitude. The information obtained was used as input for a GEANT simulation which demonstrated the feasibility of open charm physics with the proposed detector concept

This work deals with the design of a CMOS pixel sensor prototype (called MIMOSA 31) for the outer layers of the International Linear Collider (ILC) vertex detector. CMOS pixel sensors (CPS) also called monolithic active pixel sensors (MAPS) have demonstrated attractive performance towards the requirements of the vertex detector of the future linear collider. MIMOSA 31developed at IPHC-Strasbourg is the first pixel sensor integrated with 4-bit column-level ADC for the outer layers. It is composed of a matrix of 64 rows and 48 columns. The pixel concept combines in-pixel amplification with a correlated double sampling (CDS) operation in order to reduce the temporal and fixed pattern noise (FPN). At the bottom of the pixel array, each column is terminated with an analog to digital converter (ADC). The self-triggered ADC accommodating the pixel readout in a rolling shutter mode completes the conversion by performing a multi-bit/step approximation. The ADC design was optimized for power saving at sampling frequency. Accounting the fact that in the outer layers of the ILC vertex detector, the hit density is inthe order of a few per thousand, this ADC works in two modes: active mode and inactive mode. This thesis presents the details of the prototype chip and its laboratory test results.

What are the elementary particles and how did the universe originate are the main driving forces in the high energy physics. In order to further demonstrate the standard model and discover new physics, several detectors are built for the high energy physics experiments. CMOS pixel sensors (CPS) can achieve an attractive tradeoff among many performance parameters, such as readout speed, granularity, material budget, power dissipation, radiation tolerance and integrating readout circuitry on the same substrate, compared with the hybrid pixel sensors and charge coupled devices. Thus, the CPS is a good candidate for tracking the charged particles in vertex detectors and beam telescopes.The power distribution becomes an important issue in the future detectors, since a considerable amount of sensors will be installed. Unfortunately, the independent powering has been proved to fail. In order to solve the power distribution challenges and to provide noiseless voltages, this thesis focuses on the design of a low noise, limited area, low power consumption and full on-chip power management in CPS chips. The CPS are firstly introduced drawing the design requirements of the power management. The power distribution dedicated to CPS chips is then proposed, in which the power management is utilized as the second power conversion stage. Two full on-chip regulators are proposed to generate the analog power supply voltage and the reference voltage required by correlated double sampling operation, respectively. Two prototypes have verified these regulators. They can meet the requirements of CPS. Moreover, the power management techniques and the radiation tolerance design are also presented in this thesis.

El Gran Colisionador de Hadrones (LHC) tiene previsto aumentar su luminosidad hasta siete veces su valor actual con el objetivo de ampliar su actual programa de física. Esta mejora se conoce con el nombre de High Luminosity LHC (HL-LHC) y está prevista para el año 2024-2026. El actual Inner Detector (ID) del detector de ALTAS será completamente reemplazado por uno nuevo para ajustarse a los rigurosos requisitos que impone el HL-LHC. Nuevos detectores de píxeles están siendo investigados para su utilización en todo el ID cuando el HL-LHC entre en operación. La utilización de sensores de píxeles tipo monolítico dentro del ID de ATLAS supondría una nueva era para los detectores de píxeles en física de altas energías debido a sus muchas ventajas con respecto a las tecnologías que se usan actualmente. Las principales ventajas son: mejor resolución espacial, menor densidad, mayor rendimiento, y menor coste. En este contexto, un nuevo tipo de sensor monolítico conocido como Depleted Monolithic Active Pixel Sensor on silicon-on-insulator ha sido investigado en esta tesis. El capítulo 1 describe el LHC, el experimento ATLAS, y las mejoras previstas para el HL-LHC. Este capítulo también describe los requerimientos y desafíos del futuro Inner Detector, al ser el subdetector más cercano al punto de interacción. El capítulo 2 describe la base de los detectores de partículas en física de altas energías. Este capítulo abarca la interacción de partículas con la materia, los conceptos básicos para la construcción de un detector de píxeles, y la resolución de momento transverso, vértice, y parámetro de impacto de un detector. El capítulo 3 describe los daños que la radiación produce en detectores de silicio, tanto en la electrónica como en el sensor, cuyo impacto es crucial en el rendimiento de los detectores especialmente para experimentos en el HL-LHC. El capítulo 4 revisa la evolución y tendencias en detectores de pixeles, abarcando desde los ya bien establecidos pixel híbridos, hasta los CMOS píxeles. La sección dedicada a los CMOS píxeles describe los diferentes tipos que se están considerando en ATLAS: High resistivity CMOS, high voltage CMOS, y monolíticos CMOS-on-SOI. Este ultimo compone el núcleo de estudio de esta tesis y es descrito en detalle. Los siguientes capítulos detallan el programa de caracterización y medidas realizado en el contexto de esta tesis. El capitulo 5 se centra en la caracterización del daño creado por la radiación en la electrónica hasta las dosis esperadas en el ID de ATLAS durante su operación en el HL-LHC. Las propiedades del detector, como son las corrientes de fuga, el cociente entre señal y ruido, la colección de carga y la profundidad de depleción, son descritas en el capitulo 6. El Capítulo 7 describe la caracterización de sensores monolíticos CMOS-on-SOI en un haz de piones, donde la colección de carga, el reparto de carga entre píxeles, la resolución espacial, y la eficiencia son discutidas. Este trabajo concluye con un resumen, con vistas al futuro de las tecnologías monolíticas CMOS-on-SOI en la física de altas energías.
A major upgrade of the Large Hadron Collider (LHC) called High Luminosity LHC (HL-LHC) is scheduled for 2024-2026. This will lead to an increase of the luminosity by seven times the current value and to the extension of the currently ongoing physics programme. A completely new Inner Detector for the ATLAS experiment needs to be developed to withstand the extremely harsh environment at the HL-LHC. New pixel detector concepts are being investigated as a possible candidate to the inner and outer layers of the HL-LHC ATLAS Inner Detector. The use of monolithic pixel sensors in the ATLAS Inner Tracker would lead to a new era of pixel detectors as a consequence of its many advantages with respect to the current technologies. The achievement of smaller spatial resolution, lower density, bigger production yield and throughput, and smaller budget cost are the main arguments to pursue this technology. In this context, a novel Depleted Monolithic Pixel Active Detector built on a thick film Silicon-On-Insulator has been fully investigated in this thesis. Chapter 1 introduces LHC and the ATLAS experiment as well as their foreseen scenarios at the HL-LHC upgrade. This naturally motivates the stringent requirements and challenges of the closest sub-detector to the interaction point, the Inner Detector. Chapter 2 describes the basis of a tracking detector for high energy physics applications, detailing the interactions of particles with matter to the formation of a pixel detector from a semiconductor material. Then the momentum, vertex, and impact parameter resolution of a tracking detector are calculated leading to a set of requirements for the detector design. Chapter 3 describes the radiation damage in silicon detectors whose impact to the detector performance is crucial specially for HL-LHC experiments. The radiation damage in the electronics and in the silicon bulk is treated. Chapter 4 revises the current developments and trends on pixel detectors from the well established hybrid pixel technologies to the commercial CMOS pixels. The commercial CMOS pixels section describes the current technologies being considered at ATLAS: high resistivity, high voltage CMOS (currently built as hybrid and as monolithic), and monolithic CMOS-on-SOI. The latter one composes the core of study of this thesis and is described in great detail. The final chapters are dedicated to the description of the validation programme performed to the CMOS-on-SOI technology, together with characterization methods used, measurements performed, and results analysis description. Chapter 5 focuses on the measurements performed to characterize the radiation hardness of the technology against the ionizing radiation expected in the HL-LHC ATLAS detector. The crucial charge collection properties to fulfil the ATLAS detector requirements were measured and are described in Chapter 6. These measurements include leakage current, signal-to-noise ratio, collected charge, and depletion depth on unirradiated and irradiated samples. Additionally, different techniques as radioactive sources, pion beams, and laser beams were used in order to calculate the depletion depth. Chapter 7 describes the characterization of the monolithic CMOS-on-SOI in a pion beam test. The measured charge collection, charge sharing, spatial resolution, and tracking efficiency are discussed. Within the summary, an outlook towards the future of depleted monolithic active pixel sensors on silicon-on-insulator technology for high energy physics is presented.

We have realized a Data Acquisition chain for the use and characterization of APSEL4D, a 32 x 128 Monolithic Active Pixel Sensor, developed as a prototype for frontier experiments in high energy particle physics. In particular a transition board was realized for the conversion between the chip and the FPGA voltage levels and for the signal quality enhancing. A Xilinx Spartan-3 FPGA was used for real time data processing, for the chip control and the communication with a Personal Computer through a 2.0 USB port. For this purpose a firmware code, developed in VHDL language, was written. Finally a Graphical User Interface for the online system monitoring, hit display and chip control, based on windows and widgets, was realized developing a C++ code and using Qt and Qwt dedicated libraries. APSEL4D and the full acquisition chain were characterized for the first time with the electron beam of the transmission electron microscope and with 55Fe and 90Sr radioactive sources. In addition, a beam test was performed at the T9 station of the CERN PS, where hadrons of momentum of 12 GeV/c are available. The very high time resolution of APSEL4D (up to 2.5 Mfps, but used at 6 kfps) was fundamental in realizing a single electron Young experiment using nanometric double slits obtained by a FIB technique. On high statistical samples, it was possible to observe the interference and diffractions of single isolated electrons traveling inside a transmission electron microscope. For the first time, the information on the distribution of the arrival time of the single electrons has been extracted.

We have realized a Data Acquisition chain for the use and characterization of APSEL4D, a 32 x 128 Monolithic Active Pixel Sensor, developed as a prototype for frontier experiments in high energy particle physics. In particular a transition board was realized for the conversion between the chip and the FPGA voltage levels and for the signal quality enhancing. A Xilinx Spartan-3 FPGA was used for real time data processing, for the chip control and the communication with a Personal Computer through a 2.0 USB port. For this purpose a firmware code, developed in VHDL language, was written. Finally a Graphical User Interface for the online system monitoring, hit display and chip control, based on windows and widgets, was realized developing a C++ code and using Qt and Qwt dedicated libraries. APSEL4D and the full acquisition chain were characterized for the first time with the electron beam of the transmission electron microscope and with 55Fe and 90Sr radioactive sources. In addition, a beam test was performed at the T9 station of the CERN PS, where hadrons of momentum of 12 GeV/c are available. The very high time resolution of APSEL4D (up to 2.5 Mfps, but used at 6 kfps) was fundamental in realizing a single electron Young experiment using nanometric double slits obtained by a FIB technique. On high statistical samples, it was possible to observe the interference and diffractions of single isolated electrons traveling inside a transmission electron microscope. For the first time, the information on the distribution of the arrival time of the single electrons has been extracted.

ALICE (A Large Ion Collider Experiment) is dedicated to the study and characterisation of the Quark-­‐Gluon Plasma (QGP), exploiting the unique potential of ultrarelativistic heavy-­‐ion collisions at the CERN Large Hadron Collider (LHC). The increase of the LHC luminosity leading up to about 50 kHz Pb-­‐Pb interaction rate after the second long shutdown (in 2018-­‐2019) will offer the possibility to perform high precision measurements of rare probes over a wide range of momenta. These measurements are statistically limited or not even possible with the present experimental set up. For this reason, an upgrade strategy for several ALICE detectors is being pursued. In particular, it is foreseen to replace the Inner Tracking System (ITS) by a new detector which will significantly improve the tracking and vertexing capabilities of ALICE in the upgrade scenario. The new ITS will have a barrel geometry consisting of seven layers of Monolithic Active Pixel Sensors (MAPS) with high granularity, which will fulfil the material budget, readout and radiation hardness requirements for the upgrade. Intensive R&D has been carried out in the last four years on MAPS in the framework of the ALICE ITS upgrade. Various small scale sensors have been designed in the TowerJazz 0.18 um imaging sensor technology to study noise, charge collection efficiency and signal-­‐to-­‐noise ratio. This work presents the main characterization results obtained from the measurements performed on two small scale prototypes (MIMOSA-­‐32 and MIMOSA-­‐32ter) with X-­‐ray sources and beams of particles. The architecture of an innovative full scale MAPS prototype (Alice Pixel Detector, ALPIDE) is also presented that is based on an AC-­‐sensitive front end and on a hit-­‐ driven readout. The first results on the ALPIDE prototype showed that the sensor is fully functional and that it provides performance in terms of readout time, power density and noise much better than the state of the art MAPS based on the rolling shutter readout, which makes this type of sensors very attractive for employment in the new ALICE ITS.

ALICE (A Large Ion Collider Experiment) is the heavy-ion experiment at the Large Hadron Collider (LHC) at CERN. As an important part of its upgrade plans, the ALICE experiment will schedule the installation of a new Inner Tracking System (ITS) during the Long Shutdown 2 (LS2) of the LHC. The new ITS layout will consist of seven concentric layers, ¿ 12.5 Gigapixel camera covering about 10m2 with Monolithic Active Pixel Sensors (MAPS). This choice of technology has been guided by the tight requirements on the material budget of 0.3% X/X0 per layer for the three innermost layers and backed by the significant progress in the field of MAPS in recent years. The technology initially chosen for the ITS upgrade is the TowerJazz 180 nm CMOS Technology. It offers a standard epitaxial layer of 15 - 18 µm with a resistivity between 1 and 5 k¿ cm¿1 and a gate oxide thickness below 4 nm, thus being more robust to Total Ionizing Dose (TID). The main subject of this thesis is to implement a novel digital pixel readout architecture for MAPS. This thesis aims to study this novel readout architecture as an alternative to the rolling-shutter readout. However, this must be investigated through the study of several chip readout architectures during the R&D phase. Another objective of this thesis is the study and characterization of TowerJazz, if it meets the Non-Ionizing Energy Loss (NIEL) and Single Event Effects (SEE) of the ALICE ITS upgrade program. Other goals of this thesis are: ¿ Implementation of the top-down flow for this CMOS process and the design of multiple readouts for different prototypes up to the assembly of a full-scale prototype. xvii Abstract ¿ Characterization of the radiation hardness and SEE of the chips submitted to fabrication. ¿ Characterization of full custom designs using analog simulations and the generation of digital models for the simulation chain needed for the verification process. ¿ Implementation and study of different digital readouts to meet the ITS upgrade program in integration time, pixel size and power consumption, from the conceptual idea, production and fabrication phase. Chapter 1 is a brief overview of CERN, the LHC and the detectors complex. The ALICE ITS will be explained, focusing on the ITS upgrade in terms of detector needs and design constraints. Chapter 2 explains the properties of silicon detectors and the detector material and the principles of operation for MAPS. Chapters 3 and 4 describe the ALPIDE prototypes and their readout based on MAPS; this forms the central part of this work, including the multiple families of pixel detectors fabricated in order to reach the final design for the ITS. The ALPIDE3/pALPIDE3B chip, the latest MAPS chip designed, will be explained in detail, as well focusing in the matrix digital readout. In chapter 5 the noise measurements and its characterization are presented including a brief summary of detector response to irradiation with soft X-rays, sources and particle beams.
El sub detector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) es un detector de vértice y es el detector mas cercano al punto de interacción. Se encuentra conformado por 3 tipos de subdetectores, dos capas de pixel de silicio (Silicon Pixel Detectors), 2 capas de acumulación de silicio (Silicon Drift Detectors) y 2 capas de banda de Silicio (Silicon Strip Detectors). La función primaria del ITS es identificar y rastrear las partículas de bajo momentum transversal. El detector ITS en sus dos capas más internas están equipadas con sensores de silicio basados en píxeles híbridos. Para reemplazar esta tecnología de Píxeles, el detector ITS actual será reemplazado por un nuevo detector de una sola tecnología, ampliando su resolución espacial y mejorando el rastreo de trazas. Este nuevo detector constará de siete capas de sensores de píxeles activos monolíticos (MAPS), las cuales deberán satisfacer los requerimientos de presupuesto de materiales y ser tolerantes a mayores niveles de radiación para los nuevos escenarios de incrementos de luminosidad y mayores tasas de colisiones. Los sensores MAPS que integran el sensor de imagen y los circuitos de lectura se encuentran en la misma oblea de silicio, tienen grandes ventajas en una buena resolución de posición y un bajo presupuesto material en términos de bajo coste de producción. TowerJazz ofrece la posibilidad de una cuádruple-WELL aislando los transistores pMOS que se encuentran en la misma nWELL evitando la competencia con el electrodo de recolección, permitiendo circuitos mas complejos y compactos para ser implementados dentro de la zona activa y además posee una capa epitaxial de alta resistividad. Esta tecnología proporciona una puerta de óxido muy delgado limitando el daño superficial por la radiación haciéndolo adecuado para su uso denxiii Resúmen tro del experimento ALICE. En los últimos cuatro años se ha llevado a cabo una intensiva I+D en MAPS en el marco de la actualización del ITS de ALICE. Varios prototipos a pequeña escala se han desarrollado y probado exitosamente con rayos X, fuentes radioactivas y haces de partículas. La tolerancia a la radiación de ALICE ITS es moderada con una tolerancia de irradiación TID de 700 krad y NIEL de 1 × 1013 1 MeV neqcm¿2 , MAPS es una opción viable para la actualización del ITS. La contribución original de esta tesis es la implementación de una nueva arquitectura digital de lectura de píxeles para MAPS. Esta tesis presenta un codificador asíncrono de direcciones (arquitectura basada en la supresión de ceros transmitiendo la dirección de los píxeles excitados denominada PADRE) para la arquitectura ALPIDE, el autor también hizo una contribución significativa en el ensamblaje y veri- ficación de circuitos. PADRE es la principal investigación del autor, basada en un codificador de prioridad jerárquica de cuatro entradas y es una alternativa a la arquitectura de lectura rolling-shutter. Además de los prototipos a pequeña escala, también se han desarrollado prototipos a escala completa a las necesidades del detector ITS (15 mm y 30 mm) empleando un nuevo circuito de lectura basado en la versión personalizada del circuito PADRE. El pALPIDEfs fue el primer prototipo a escala completa y se caracterizó obteniendo un tiempo de lectura de la matriz por debajo de 4 µs y un consumo de energía en el orden de 80 mWcm¿2 . En general, los resultados obtenidos representan un avance significativo de la tecnología MAPS en cuanto al consumo de energía, velocidad de lectura, tiempo de recolección de carga y tolerancia a la radiación. El sensor pALPIDE2 ha demostrado ser una opción muy atractiva para el nuevo detector ITS, satisfaciendo los requerimientos en términos de eficiencia de detección, fake-hit rate y resolución de posición, ya que su rendimiento no puede alcanzarse mediante prototipos basados en la arquitectura de lectura tradicionales como es
El subdetector ITS (Inner Tracking System) del detector ALICE (A Large Ion Collider Experiment) és un detector de vèrtex i és el detector mes proper al punt d'interacció. Es troba conformat per 3 tipus de subdetectors, dues capes de píxel de silici (Silicon Pixel Detectors), 2 capes d'acumulació de silici (Silicon Drift Detectors) i 2 capes de banda de Silici (Silicon Strip Detectors). La funció primària del ITS és identificar i rastrejar les partícules de baix moment transversal. El detector ITS en les seues dues capes més internes estan equipades amb sensors de silici basats en píxels híbrids. Per a reemplaçar aquesta tecnologia de Píxels, el detector ITS actual serà reemplaçat per un nou detector d'una sola tecnologia, ampliant la seua resolució espacial i millorant el rastreig de traces. Aquest nou detector constarà de set capes de sensors de píxels actius monolítics (MAPS), les quals hauran de satisfer els requeriments de pressupost de materials i ser tolerants a majors nivells de radiació per als nous escenaris d'increments de lluminositat i majors taxes de col·lisions. Els sensors MAPS que integren el sensor d'imatge i els circuits de lectura es troben en la mateixa hòstia de silici, tenen grans avantatges en una bona resolució de posició i un baix pressupost material en termes de baix cost de producció. TowerJazz ofereix la possibilitat d'una quàdruple-WELL aïllant els transistors pMOS que es troben en la mateixa nWELL evitant la competència amb l'elèctrode de recol·lecció, permetent circuits mes complexos i compactes per a ser implementats dins de la zona activa i a més posseeix una capa epitaxial d'alta resistivitat. Aquesta tecnologia proporciona una porta d'òxid molt prim limitant el dany superficial per la radiació fent-ho adequat per al seu ús dins de l'- experiment ALICE. En els últims quatre anys s'ha dut a terme una intensiva R+D en MAPS en el marc de l'actualització del ITS d'ALICE. Diversos prototips a petita escala s'han desenvolupat i provat ix Resum reeixidament amb rajos X, fonts radioactives i feixos de partícules. La tolerància a la radiació d'ALICE ITS és moderada amb una tolerància d'irradiació TID de 700 krad i NIEL d'1× 1013 1MeV neqcm¿2 , MAPS és una opció viable per a l'actualització del ITS. La contribució original d'aquesta tesi és la implementació d'una nova arquitectura digital de lectura de píxels per a MAPS. Aquesta tesi presenta un codificador asíncron d'adreces (arquitectura basada en la supressió de zeros transmetent l'adreça dels píxels excitats denominada PADRE) per a l'arquitectura ALPIDE, l'autor també va fer una contribució significativa en l'assemblatge i verificació de circuits. PADRE és la principal recerca de l'autor, basada en un codificador de prioritat jeràrquica de quatre entrades i és una alternativa a l'arquitectura de lectura rolling-shutter. A més dels prototips a petita escala, també s'han desenvolupat prototips a escala completa a les necessitats del detector ITS (15 mm i 30 mm) emprant un nou circuit de lectura basat en la versió personalitzada del circuit PADRE. El pALPIDEfs va ser el primer prototip a escala completa i es va caracteritzar obtenint un temps de lectura de la matriu per sota de 4 µs i un consum d'energia en l'ordre de 80 mWcm¿2 . En general, els resultats obtinguts representen un avanç significatiu de la tecnologia MAPS quant al consum d'energia, velocitat de lectura, temps de recol·lecció de càrrega i tolerància a la radiació. El sensor pALPIDE2 ha demostrat ser una opció molt atractiva per al nou detector ITS, satisfent els requeriments en termes d'eficiència de detecció, fake-hit rate i resolució de posició, ja que el seu rendiment no pot aconseguir-se mitjançant prototips basats en l'arquitectura de lectura tradicionals com és el rolling-shutter dissenyat en la mateixa tecnologia. Per aquesta raó, la R+D en els prototips ALPIDE ha continuat amb l'objectiu d'optimitza
Marín Tobón, CA. (2017). PADRE pixel read-out architecture for Monolithic Active Pixel Sensor for the new ALICE Inner Tracking System in TowerJazz 180 nm technolog [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86154
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