72 research outputs found
When linearity prevails over hierarchy in syntax
Hierarchical structure has been cherished as a grammatical universal. We use experimental methods to show where linear order is also a relevant syntactic relation. An identical methodology and design were used across six research sites on South Slavic languages. Experimental results show that in certain configurations, grammatical production can in fact favor linear order over hierarchical structure. However, these findings are limited to coordinate structures and distinct from the kind of production errors found with comparable configurations such as “attraction” errors. The results demonstrate that agreement morphology may be computed in a series of steps, one of which is partly independent from syntactic hierarchy
MALTA monolithic pixel sensors in TowerJazz 180 nm technology
Depleted Monolithic Active Pixel Sensors are of highest interest at the HL-LHC and beyond for the replacement of the Pixel trackers in the outermost layers of experiments where the requirement on total area and cost effectiveness is much bigger. They aim to provide high granularity and low material budget over large surfaces with ease of integration. Our research focuses on MALTA, a radiation hard DMAPS with small collection electrode designed in TowerJazz 180 nm CMOS imaging technology and asynchronous read-out. Latest prototypes are radiation hard up to 2 Ă— 1015 1 MeV neq/cm2 with a time resolution better than 2 ns
Timing performance of radiation hard MALTA monolithic Pixel sensors
The MALTA family of Depleted Monolithic Active Pixel Sensor (DMAPS) produced
in Tower 180 nm CMOS technology targets radiation hard applications for the
HL-LHC and beyond. Several process modifications and front-end improvements
have resulted in radiation hardness up to and time resolution below 2 ns,
with uniform charge collection efficiency across the Pixel of size with a electrode size. The MALTA2
demonstrator produced in 2021 on high-resistivity epitaxial silicon and on
Czochralski substrates implements a new cascoded front-end that reduces the RTS
noise and has a higher gain. This contribution shows results from MALTA2 on
timing resolution at the nanosecond level from the CERN SPS test-beam campaign
of 2021.Comment: 8 pages, 8 figures. Submitted to Journal of Instrumentation (JINST).
Proceedings of the 23rd International Workshop on Radiation Imaging Detectors
IWORID 202
Depletion depth studies with the MALTA2 sensor, a depleted monolithic active pixel sensor
MALTA2 is a depleted monolithic active pixel sensor (DMAPS) developed in the Tower 180 nm CMOS imaging process. Monolithic CMOS sensors offer advantages over current hybrid imaging sensors both in terms of increased tracking performance due to lower material budget but also in terms of ease of integration and construction costs due to the monolithic design. Current research and development efforts are aimed towards radiation-hard designs up to 100 Mrad in Total Ionizing Dose and 3 × 1015 1 MeV neq / cm2 in Non-Ionizing Energy Loss. One important property of a sensor’s radiation hardness is the depletion depth at which efficient charge collection is achieved via drift movement. Grazing angle test-beam data was taken during the 2023 SPS CERN test beam with the MALTA telescope and Edge Transient Current Technique studies were performed at DESY in order to develop a quantitative study of the depletion depth for un-irradiated, epitaxial MALTA2 samples. The study is planned to be extended for irradiated and Czochralski MALTA2 samples
Latest developments and characterisation results of DMAPS in TowerJazz 180nm for High Luminosity LHC
The last couple of years have seen the development of Depleted Monolithic Active Pixel Sensors (DMAPS) fabricated in TowerJazz 180nm with a process modification to increase the radiation tolerance. While many of MAPS developments focus on low radiation environment, we have taken the development to high radiation environment like pp-experiments at High Luminosity LHC. DMAPS are a cost effective and lightweight alternative to state-of-the-art hybrid detectors if they can fulfil the given requirements for radiation hardness, signal response time and hit rate capability. The MALTA and Mini-MALTA sensors have shown excellent detection efficiency after irradiation to the life time dose expected at the outer layers of the ATLAS pixel tracker Upgrade. Our development focuses on providing large pixel matrixes with excellent time resolution (<2ns) and tracking. This publication will discuss characterisation results of the DMAPS devices with special focus on the new MALTA2 sensor and will show the path of future development
A 1-ÎĽW radiation-hard front-end in a 0.18-ÎĽm CMOS process for the MALTA2 monolithic sensor
In this article, a low-power, radiation-hard front-end circuit for monolithic pixel sensors, designed to meet the requirements of low noise and low pixel-to-pixel variability, the key features to achieve high detection efficiencies, is presented. The sensor features a small collection electrode to achieve a small capacitance (<5 fF) and allows full CMOS in-pixel circuitry. The circuit is implemented in the 180-nm CMOS imaging technology from the TowerJazz foundry and integrated into the MALTA2 chip, which is part of a development that targets the specifications of the outer pixel layer of the ATLAS Inner Tracker upgrade at the LHC. One of the main challenges for monolithic sensors is a radiation hardness up to 1015 1-MeV neq/cm2 non-ionizing energy loss (NIEL) and 80 Mrad total ionizing dose (TID) required for this application. Tests up to 3â‹…1015 1-MeV neq/cm2 and 100 Mrad were performed on the MALTA2 sensor and front-end circuit, which still show good performance even after these levels of irradiation, promising for even more demanding applications such as the future experiments at the high-luminosity large hadron collider (HL-LHC)
Future developments of radiation tolerant sensors based on the MALTA architecture
The planned MALTA3 DMAPS designed in the standard TowerJazz 180 nm imaging process will implement the numerous process modifications, as well as front-end changes in order to boost the charge collection efficiency after the targeted fluence of 1 × 1015 1 MeV neq/cm2. The effectiveness of these changes have been demonstrated with recent measurements of the full size MALTA2 chip. With the original MALTA concept being fully asynchronous, a small-scale MiniMALTA demonstrator chip has been developed with the intention of bridging the gap between the asynchronous pixel matrix, and the synchronous DAQ. This readout architecture will serve as a baseline for MALTA3, with focus on improved timing performance. The synchronization memory has been upgraded to allow clock speeds of up to 1.28 GHz, with the goal of achieving a sub-nanosecond on-chip timing resolution. The subsequent digital readout chain has been modified and will be discussed in the context of the overall sensor architecture
Development of a large-area, light-weight module using the MALTA monolithic pixel detector
The MALTA pixel chip is a 2 cm x 2 cm large monolithic pixel detector developed in the Tower 180 nm imaging process. The chip contains four CMOS transceiver blocks at its sides which allow chip-to-chip data transfer. The power pads are located mainly at the side edges on the chip which allows for chip-to-chip power transmission. The MALTA chip has been used to study module assembly using different interconnection techniques to transmit data and power from chip to chip and to minimize the overall material budget. Several 2-chip and 4-chip modules have been assembled using standard wire bonding, ACF (Anisotropic Conductive Films) and laser reflow interconnection techniques. These proceedings will summarize the experience with the different interconnection techniques and performance tests of MALTA modules with 2 and 4 chips tested in a cosmic muon telescope. They will also show first results on the effect of serial power tests on chip performance as well as the impact of the different interconnection techniques and the results of mechanical tests. Finally, a conceptual study for a flex based ultra-light weight monolithic pixel module based on the MALTA chip with minimum interconnections is presented
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