IMB-CNM PhD Thesis Defense by Jairo Antonio Villegas Dominguez: Development of Low Gain Avalanche Detectors (LGAD) for high- and low-penetrating particles in silicon
Directors:
- Salvador Hidalgo
- Giulio Pellegrini
Tribunal:
- President: Prof. Iván Vila (IFCA-CSIC)
- Secretary: Prof. Montserrat Nafría (UAB)
- Vocal: Dra. Celeste Fleta (IMB-CNM-CSIC)
Abstract:
This thesis presents the development of Low Gain Avalanche Detectors (LGAD) at the Institute of Microelectronics of Barcelona (IMB-CNM). The work is primarily focused on the design, optimization and fabrication of LGAD sensors for High Energy Physics (HEP) experiments and, specifically, for High-Luminosity Large Hadron Collider (HL-LHC) experiments at CERN. The HL-LHC aims to upgrade in the next few years, increasing its luminosity to enable the collection of more data in shorter time frames which, in turns, will increase the likelihood of new particle discoveries. Consequently, the silicon detectors used in HL-LHC experiments must demonstrate exceptional radiation tolerance as well as tracking and timing performance to prevent pile-up effects, being the LGAD a great candidate to fulfi ll such zealous task.
While the primary focus of LGAD development has been HEP experiments, these detectors also offer potential applications beyond this fi eld. Specifically, LGADs hold promise for detecting low-penetrating particles in silicon. To accommodate these applications, a redesign of the LGAD was necessary, as it was originally optimized exclusively for HEP experiments. As a result, the nLGAD was first developed at IMB-CNM, which retains the excellent performance of traditional LGAD devices while being specifically optimized to detect low-penetrating particles. The design, optimization and fabrication of IMB-CNM nLGAD sensors represent a significant aspect of this thesis.
Additionally, an LGAD or nLGAD can be technologically tailored to achieve a fill factor of 100 %, which is crucial for applications requiring enhanced silicon detector sensitivity. This thesis will specifically address the potential of the Trench iLGAD (TiLGAD) in achieving this goal.
Overall, this work will cover the design, simulation, optimization, fabrication and characterization of IMB-CNM LGAD sensors across various technological configurations, each tailored to address specifi c key issues in the realm of particle detection.