Beam test results of 25 $\mu$m and 35 $\mu$m thick FBK UFSD]{Beam test results of 25 $\mu$m and 35 $\mu$m thick FBK ultra fast silicon detectors

TL;DR

This study evaluates the timing performance of ultra-thin UFSDs of 25 and 35 micrometers thickness, demonstrating time resolutions around 22-25 ps in beam tests at CERN, with potential for high-precision timing applications.

Contribution

First beam test results of ultra-thin UFSDs with 25 and 35 micrometers thickness, showing their timing capabilities and voltage dependence.

Findings

Time resolution of ~25 ps for 25 μm UFSD at 120 V

Time resolution of ~22 ps for 35 μm UFSD at 240 V

Performance comparable to thicker reference sensors

Abstract

This paper presents the measurements on first very thin Ultra Fast Silicon Detectors (UFSDs) produced by Fondazione Bruno Kessler; the data have been collected in a beam test setup at the CERN PS, using beam with a momentum of 12 GeV/c. UFSDs with a nominal thickness of 25 $\mu$m and 35 $\mu$m and an area of 1 $\times$ 1 $\text{mm}^2$ have been considered, together with an additional HPK 50-$\mu$m thick sensor, taken as reference. Their timing performances have been studied as a function of the applied voltage and gain. A time resolution of about 25 ps and of 22 ps at a voltage of 120 V and 240 V has been obtained for the 25 and 35 $\mu$m thick UFSDs, respectively.