Speaker
Description
Low Gain Avalanche Detectors (LGADs) are being extensively studied due to their unique charge amplification capability arising from the high electric field region created by the gain layer. Owing to their excellent timing and tracking performance, these detectors are expected to play a crucial role in the harsh radiation environments of current and future generations of high-energy physics (HEP) experiments. However, the charge multiplication characteristics of LGADs are significantly affected by the unprecedented fluences of hadrons encountered in such environments. Experimental investigations have shown that the thick LGADs (300 µm) gradually lose their charge multiplication advantage at the neutron fluences of the order of 10^15 n_eq " " cm^(-2).
In the present work, the Silvaco TCAD simulation framework is used to investigate the performance of both non-irradiated and neutron-irradiated LGADs with various detector thicknesses and different gain layer design parameters. The performance of these device configurations is evaluated through the analysis of their charge collection (CC) behaviour as well as the electrical responses, including the current–voltage (IV) and capacitance–voltage (CV) characteristics.
To account for the effects of neutron irradiation in simulations, a recently developed comprehensive neutron radiation damage model is implemented. In addition to incorporating fluence-dependent parametric values for the impact ionization coefficients, specifically optimized for LGADs, the model also describes the acceptor removal mechanism in the gain layer along with the bulk damage effects induced by the neutron irradiation.
The reported study provides useful insights into the radiation tolerance and optimization of LGAD designs and can serve as a valuable reference for the development of radiation-hard silicon detectors for present and future high-energy physics and collider experiments.