Comprehensive technology study of radiation hard LGADs

TL;DR

This study investigates the radiation tolerance of LGAD sensors with different dopants, analyzing their electrical and timing performance under neutron and proton irradiation to identify stability and gain reduction mechanisms.

Contribution

It provides a comparative analysis of LGADs with boron, boron + carbon, and gallium gain layers under radiation, highlighting their stability and performance degradation.

Findings

Boron + carbon LGADs show improved radiation stability.

Gain reduction correlates with acceptor removal at high fluences.

Timing performance remains acceptable up to certain radiation levels.

Abstract

Towards radiation tolerant sensors for pico-second timing, several dopants are explored. Using a common mask, CNM produced LGADs with boron, boron + carbon and gallium implanted gain layers are studied under neutron and proton irradiation. With fluences ranging from $10^{14}$ to $6\times 10^{15} n_{eq}/cm^{2}$ on both particle species, reported results focus on acceptor removal and gain reduction via electrical characterization. Timing performance, charge collection, gain and relative efficiency are treated through charged particle measurements, including signal analysis and noise characterization. An accent is placed on stability, via dark rate and operating voltage studies while, radiation related gain reduction mechanisms are examined comparing gain estimations through different approaches.