FE-I4 chip design

Proceedings of The 21st International Workshop on Vertex Detectors — PoS(Vertex 2012)

The ATLAS FE-I4 ASIC is a novel pixel detector readout chip designed in a CMOS 130 nm feature size process. The chip is able to cope with high hit rate and withstand the harsh radiation environment in close proximity to the interaction point at LHC. FE-I4 will find its first application with ATLAS IBL, an additional innermost pixel layer scheduled for installation in 2013, but is also suited for the intermediate radii pixel layers for future upgrades. In this paper, the modular design concept of FE-I4 is introduced and its readout architecture, analog performance and radiation hardness are discussed. After the successful development of the first full-scale prototype version of the chip in 2010, the production version for IBL (FE-I4B) has recently become available. Here, we review the main design choices for FE-I4B and present first testing results.

Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment, 2011

A new pixel readout integrated circuit denominated FE-I4 is being designed to meet the requirements of ATLAS experiment upgrades. It will be the largest readout IC produced to date for particle physics applications, filling the maximum allowed reticle area. This will significantly reduce the cost of future hybrid pixel detectors. In addition, FE-I4 will have smaller pixels and higher rate capability than the present generation of LHC pixel detectors. Design features are described along with simulation and test results, including low power and high rate readout architecture, mixed signal design strategy, and yield hardening.

2023

In the ATLAS detector upgrade for the High-Luminosity LHC (HL-LHC), the current Inner Detector will be replaced with an all-silicon Inner Tracker (ITk), to operate under higher occupancy (instantaneous luminosity 7.5 × 10 34 cm −2 s −1 , which corresponds to about 200 inelastic pp collisions per bunch crossing) and radiation damage (particle fluence up to 2 × 10 16 n eq /cm 2). The data taking is planned to start in 2029 and last for 10 years. The innermost part of the ITk will be equipped with pixel modules, consisting of pixel sensors and novel ASICs, implemented in 65 nm CMOS technology. The ITk project is currently in pre-production stage. To assure that specifications will be met during production, sensors and test structures from different vendors were sent to different sites for irradiation, hybridisation and follow-up testing. This paper presents the results of the characterisation of the pre-production planar sensor for ITk.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2018

Pixel sensors based on commercial high-voltage CMOS processes are an exciting technology that is considered as an option for the outer layer of the ATLAS inner tracker upgrade at the High Luminosity LHC. Here, charged particles are detected using deep n-wells as sensor diodes with the depleted region extending into the silicon bulk. Both analog and digital readout electronics can be added to achieve different levels of integration up to a fully monolithic sensor. Small scale prototypes using the ams CMOS technology have previously demonstrated that it can achieve the required radiation tolerance of 10 15 n eq /cm 2 and detection efficiencies above 99.5 %. Recently, large area prototypes, comparable in size to a full sensor, have been produced that include most features required towards a final design: the H35demo prototype produced in ams H35 technology that supports both external and integrated readout and the monolithic ATLASPix1 pre-production design produced in ams aH18 technology. Both chips are based on large fillfactor pixel designs, but differ in readout structure. Performance results for H35DEMO with capacitively-coupled external readout and first results for the monolithic ATLASPix1 are shown.

2013

The ATLAS Pixel Detector is the innermost detector of the ATLAS experiment at the Large Hadron Collider at CERN. The detector provides hermetic coverage with three cylindrical layers and three layers of forward and backward pixel detectors. It consists of approximately 80 millions pixels that are individually read out via chips bump-bonded to 1744 n-in-n silicon substrates. Intensive calibration, tuning, timing optimization and monitoring resulted in the successful five years operation with good detector performance. The record breaking instantaneous luminosities of 7.7 • 10 33 cm -2 s -1 recently surpassed at the LHC generate a rapidly increasing particle fluence in the ATLAS Pixel Detector. As the radiation dose accumulates, the first effects of radiation damage are now observable in the silicon sensors as an increase in the silicon leakage current and the change of the voltage required to fully deplete the sensor. The fourth pixel layer at the radius of 3.3 cm will be added during the long shutdown 2013-2014 together with the replacement of pixel services. Letter of Intent was submitted for the completely new Pixel Detector after 2023, capable to take data with extremely high leveled luminosities of 5 • 10 34 cm -2 s -1 at High Luminosity LHC.

Journal of Instrumentation, 2012

The FE-I4 is a new pixel readout integrated circuit designed to meet the requirements of ATLAS experiment upgrades. The first samples of the FE-I4 engineering run (called FE-I4A) delivered promising results in terms of the requested performances. The FE-I4 team envisaged a number of modifications and fine-tuning before the actual exploitation, planned within the Insertable B-Layer (IBL) of ATLAS. As

Journal of Instrumentation, 2014

Journal of Instrumentation, 2015

Journal of Instrumentation, 2008

The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2019

The upgrade of the ATLAS experiment for the operation at the High Luminosity Large Hadron Collider requires a new and more performant inner tracker, the ITk. The innermost part of this tracker will be built using silicon pixel detectors. This paper describes the ITk pixel project, which, after few years of design and test effort, is now defined in detail.