ATLAS

Abstract:

For the Inner Tracking System 3 (ITS3) upgrade, the ALICE experiment at CERN requires monolithic active pixel sensors of dimensions up to 97 mm×266 mm, occupying a large fraction of a 300 mm wafer. To manufacture such a wafer-scale device, larger than the single design reticle size, stitching is employed. The MOnolithic Stitched Sensor (MOSS) is a prototype silicon pixel sensor of 14 mm×259 mm size with the primary goal of understanding the stitching technique and yield. Given the large size, high yield is paramount for the ITS3 sensors, and an in-depth yield characterization was performed on these MOSS sensors. In a collaborative effort, the foundry adapted the metal stack to the requirements of the project, but recurrent fault signatures were discovered with various frequencies across all 20 wafers tested, and correlated through dedicated measurements and analyses. Following these findings, the foundry implemented a mitigation strategy to avoid the issue in the future. This article does not describe process details but concentrates on the measurements and analysis method.

Abstract:

In this paper we review the physics opportunities at linear e+e−$$\mathrm{e}^{+}\mathrm{e}^{-} $$ colliders with a special focus on high centre-of-mass energies and beam polarisation, take a fresh look at the various accelerator technologies available or under development and, for the first time, discuss how a facility first equipped with a technology that is mature today could be upgraded with technologies of tomorrow to reach much higher energies and/or luminosities. In addition, we discuss detectors, alternative collider modes, as well as opportunities for beyond-collider experiments and R&D facilities as part of a linear collider facility (LCF). The material of this paper supports all plans for e+e−$$\mathrm{e}^{+}\mathrm{e}^{-} $$ linear colliders and the additional opportunities they offer, independently of technology choice or proposed site, as well as R&D for advanced accelerator technologies. This joint perspective on the physics goals, early technologies and upgrade strategies has been developed by the LCVision team based on an initial discussion at LCWS2024 in Tokyo and a follow-up at the LCVision Community Event at CERN in January 2025. It heavily builds on decades of achievements of the global linear collider community, in particular in the context of CLIC and ILC.