Resistive Read-out in Thin Silicon Sensors with Internal Gain

TL;DR

This paper discusses innovations in silicon sensors, combining low-gain avalanche diodes and resistive read-out to enhance temporal and spatial resolution for future high-energy physics experiments.

Contribution

It introduces the second FBK production of resistive silicon detectors and demonstrates their combined high temporal and spatial resolution capabilities.

Findings

Achieved 30 ps temporal resolution with 1x1 mm² pixels.

Demonstrated spatial resolution of 30 microns.

Validated the effectiveness of combined LGAD and RSD technologies.

Abstract

Two design innovations, low-gain avalanche (Low-Gain Avalance Diode, LGAD) and resistive read-out (Resistive Silicon Detector, RSD), have brought strong performance improvements to silicon sensors. Large signals, due to the added gain mechanism, lead to improved temporal precision, while charge sharing, introduced by resistive read-out, allows for achieving excellent spatial resolution even with large pixels. LGAD- and RSD- based silicon sensors are now adopted, or considered, in several future experiments and are the basis for almost every next 4D-trackers. New results obtained with sensors belonging to the second FBK production of RSD (RSD2) demonstrate how a combined resolution of 30 ps and 30 \microns can be obtained with pixels as large as $1 \times 1 $ mm$^2$.