Depleted fully monolithic CMOS pixel detectors using a column based readout architecture for the ATLAS Inner Tracker upgrade

TL;DR

This paper presents two prototypes of depleted monolithic CMOS pixel sensors, LF-MonoPix and TJ-MonoPix, designed for the ATLAS Inner Tracker upgrade, demonstrating their architecture and initial performance in high-radiation environments.

Contribution

It introduces two new DMAPS prototypes with different CMOS technologies and describes their design, architecture, and initial measurement results for high-luminosity collider applications.

Findings

LF-MonoPix fabricated in 150 nm CMOS technology.

TJ-MonoPix fabricated in 180 nm CMOS technology.

Initial measurements show promising performance for high-radiation environments.

Abstract

Depleted monolithic active pixel sensors (DMAPS), which exploit high voltage and/or high resistivity add-ons of modern CMOS technologies to achieve substantial depletion in the sensing volume, have proven to have high radiation tolerance towards the requirements of ATLAS in the high-luminosity LHC era. Depleted fully monolithic CMOS pixels with fast readout architectures are currently being developed as promising candidates for the outer pixel layers of the future ATLAS Inner Tracker, which will be installed during the phase II upgrade of ATLAS around year 2025. In this work, two DMAPS prototype designs, named LF-MonoPix and TJ-MonoPix, are presented. LF-MonoPix was designed and fabricated in the LFoundry 150~nm CMOS technology, and TJ-MonoPix has been designed in the TowerJazz 180~nm CMOS technology. Both chips employ the same readout architecture, i.e. the column drain architecture, whereas different sensor implementation concepts are pursued. The design of the two prototypes will be described. First measurement results for LF-MonoPix will also be shown.