Recent Technological Developments on LGAD and iLGAD Detectors for Tracking and Timing Applications

TL;DR

This paper discusses recent advancements in LGAD and introduces the novel iLGAD architecture, both based on avalanche diode principles, with detailed simulations and measurements for high-precision timing and tracking applications.

Contribution

It presents the latest technological developments in LGAD and introduces the innovative inverse-LGAD (iLGAD) architecture, expanding capabilities for timing and tracking detectors.

Findings

LGAD structures optimized for sub-30 ps timing resolution

Introduction of the inverse-LGAD architecture

Comprehensive TCAD simulations and experimental validation

Abstract

This paper reports the last technological development on the Low Gain Avalanche Detector (LGAD) and introduces a new architecture of these detectors called inverse-LGAD (iLGAD). Both approaches are based on the standard Avalanche Photo Diodes (APD) concept, commonly used in optical and X-ray detection applications, including an internal multiplication of the charge generated by radiation. The multiplication is inherent to the basic n++-p+-p structure, where the doping profile of the p+ layer is optimized to achieve high field and high impact ionization at the junction. The LGAD structures are optimized for applications such as tracking or timing detectors for high energy physics experiments or medical applications where time resolution lower than 30 ps is required. Detailed TCAD device simulations together with the electrical and charge collection measurements are presented through this work.