Technical design of the phase I Mu3e experiment

Nuclear instruments & methods in physics research / A 1014, 165679 (2021). doi:10.1016/j.nima.2021.165679

Irradiation study of a fully monolithic HV-CMOS pixel sensor design in AMS 180 nm

Abstract High-Voltage Monolithic Active Pixel Sensors (HV-MAPS) based on a 180 nm HV-CMOS process have been proposed to realize thin, fast and highly integrated pixel sensors. The MuPix7 prototype, fabricated in the commercial AMS H18 process, features a fully integrated on-chip readout, i.e. hit-digitization, zero suppression and data serialization. MuPix7 is the first fully monolithic HV-CMOS pixel sensor that has been tested for the use in high irradiation environments like HL-LHC. We present results from laboratory and test beam measurements of MuPix7 prototypes irradiated with neutrons (up to 5.0 × 1015 neq/cm2) and 24 GeV protons (up to 7.8 × 1015 protons/cm2) and compare the performa…

MuPix and ATLASPix -- Architectures and Results

High Voltage Monolithic Active Pixel Sensors (HV-MAPS) are based on a commercial High Voltage CMOS process and collect charge by drift inside a reversely biased diode. HV-MAPS represent a promising technology for future pixel tracking detectors. Two recent developments are presented. The MuPix has a continuous readout and is being developed for the Mu3e experiment whereas the ATLASPix is being developed for LHC applications with a triggered readout. Both variants have a fully monolithic design including state machines, clock circuitries and serial drivers. Several prototypes and design variants were characterised in the lab and in testbeam campaigns to measure efficiencies, noise, time reso…

Performance of the ATLASPix1 pixel sensor prototype in ams aH18 CMOS technology for the ATLAS ITk upgrade

The MuPix System-on-Chip for the Mu3e Experiment

Nuclear instruments & methods in physics research / A 845, 194 - 198 (2016). doi:10.1016/j.nima.2016.06.095

The MuPix Telescope: A Thin, high Rate Tracking Telescope

The MuPix Telescope is a particle tracking telescope, optimized for tracking low momentum particles and high rates. It is based on the novel High-Voltage Monolithic Active Pixel Sensors (HV-MAPS), designed for the Mu3e tracking detector. The telescope represents a first application of the HV-MAPS technology and also serves as test bed of the Mu3e readout chain. The telescope consists of up to eight layers of the newest prototypes, the MuPix7 sensors, which send data self-triggered via fast serial links to FPGAs, where the data is time-ordered and sent to the PC. A particle hit rate of 1 MHz per layer could be processed. Online tracking is performed with a subset of the incoming data. The ge…

Efficiency and timing performance of the MuPix7 high-voltage monolithic active pixel sensor

The MuPix7 is a prototype high voltage monolithic active pixel sensor with 103 times 80 um2 pixels thinned to 64 um and incorporating the complete read-out circuitry including a 1.25 Gbit/s differential data link. Using data taken at the DESY electron test beam, we demonstrate an efficiency of 99.3% and a time resolution of 14 ns. The efficiency and time resolution are studied with sub-pixel resolution and reproduced in simulations.

Performance of the large scale HV-CMOS pixel sensor MuPix8

The Mu3e experiment is searching for the charged lepton flavour violating decay $ ��^+\rightarrow e^+ e^- e^+ $, aiming for an ultimate sensitivity of one in $10^{16}$ decays. In an environment of up to $10^9$ muon decays per second the detector needs to provide precise vertex, time and momentum information to suppress accidental and physics background. The detector consists of cylindrical layers of $50\, ��\text{m}$ thin High Voltage Monolithic Active Pixel Sensors (HV-MAPS) placed in a $1\,\text{T}$ magnetic field. The measurement of the trajectories of the decay particles allows for a precise vertex and momentum reconstruction. Additional layers of fast scintillating fibre and tile detec…

MuPix8 — Large area monolithic HVCMOS pixel detector for the Mu3e experiment

Abstract The requirements of the ultra thin pixel detectors for the Mu3e experiment at PSI can be achieved by the HVCMOS technology, which allows the design of fast monolithic detectors. The latest nearly full size prototype, MuPix8, has a size of about 1 × 2 cm 2 . The pixel readout circuitry was fully redesigned in comparison to the previous MuPix versions. MuPix8’s readout electronics implement a new concept with two comparators and two different operation modes. One mode uses two threshold voltages for time walk correction, the other is a ramp-ADC. First tests show a detection efficiency of 99.6% for 4 GeV electrons.

MuPix7 - A fast monolithic HV-CMOS pixel chip for Mu3e

The MuPix7 chip is a monolithic HV-CMOS pixel chip, thinned down to 50 \mu m. It provides continuous self-triggered, non-shuttered readout at rates up to 30 Mhits/chip of 3x3 mm^2 active area and a pixel size of 103x80 \mu m^2. The hit efficiency depends on the chosen working point. Settings with a power consumption of 300 mW/cm^2 allow for a hit efficiency >99.5%. A time resolution of 14.2 ns (Gaussian sigma) is achieved. Latest results from 2016 test beam campaigns are shown.