Signal formation and sharing in AC-LGADs using the ALTIROC 0 front-end chip

TL;DR

This paper reports the first successful readout of AC-LGAD sensors using the ALTIROC 0 chip, demonstrating potential for advanced 4D detectors in various scientific fields.

Contribution

It demonstrates the first successful integration of AC-LGAD sensors with the ALTIROC 0 readout chip, enabling high-resolution 4D detection capabilities.

Findings

Successful readout of AC-LGAD sensors with ALTIROC 0

Analysis of signals from beta sources and laser

Paves the way for next-generation 4D detectors

Abstract

The development of detectors that provide high resolution in four dimensions has attracted wide-spread interest in the scientific community for applications in high-energy physics, nuclear physics, medical imaging, mass spectroscopy as well as quantum information. However, finding a technology capable of fulfilling such aspiration proved to be an arduous task. Among other silicon-based candidates, the Low-Gain Avalanche Diode (LGAD) has already shown excellent timing performances but proved to be unsuitable for fine pixelization. Therefore, the AC-coupled LGAD (AC-LGAD) approach was introduced to provide high resolution in both time and space, making it a promising candidate for future 4D detectors. However, appropriate readout electronics must be developed to match the sensor's fast-time and fine-pitch capabilities. This is currently a major technological challenge. In this paper, we test AC-LGAD prototypes read out by the fast-time ASIC ALTIROC 0, originally developed for the readout of DC-coupled LGADs for the ATLAS experiment at the HL-LHC. Signal generated by either betas from a $^{90}$Sr source or a focused infra-red laser were analyzed. This paper details the first successful readout of an AC-LGAD sensor using a readout chip. This result will pave the way for the design and construction of a new generation of AC-LGAD-based 4D detectors.