학술논문

A Two-Prong Approach to the Simulation of DC-RSD: TCAD and SPICE
Document Type
Periodical
Source
IEEE Transactions on Nuclear Science IEEE Trans. Nucl. Sci. Nuclear Science, IEEE Transactions on. 71(2):127-134 Feb, 2024
Subject
Nuclear Engineering
Bioengineering
Solid modeling
Silicon
Resistance
Fill factor (solar cell)
Spatial resolution
Detectors
Timing
4-D tracking
AC-coupled RSD (RSD)
DC-coupled readout
low-gain avalanche diode (LGAD)
solid-state silicon detectors
SPICE simulation
technology-CAD (TCAD) simulation
Language
ISSN
0018-9499
1558-1578
Abstract
The DC-coupled resistive silicon detectors (DC-RSD) are the evolution of the AC-coupled RSD (RSD) design, both based on the low-gain avalanche diode (LGAD) technology. The DC-RSD design concept intends to address a few known issues present in RSDs (e.g., baseline fluctuation and long tail-bipolar signals) while maintaining their advantages (e.g., signal spreading and 100% fill factor). The simulation of DC-RSD presents several unique challenges linked to the complex nature of its design and the large pixel size. The defining feature of DC-RSD, charge sharing over distances that can be as large as a millimeter, represents a formidable challenge for technology CAD (TCAD), the standard simulation tool. To circumvent this problem, we have developed a mixed-mode approach to the DC-RSD simulation, which exploits a combination of two simulation tools: TCAD and SPICE. Thanks to this hybrid approach, it has been possible to demonstrate that, according to the simulation, the key features of the RSD—excellent timing and spatial resolutions (few tens of picoseconds and few microns)—are maintained in the DC-RSD design. In this work, we present the developed models and methodology, mainly showing the results of device-level numerical simulation, which have been obtained with the state-of-the-art Synopsys Sentaurus TCAD suite of tools. Such results will provide all the necessary information for the first batch of DC-RSD produced by the Fondazione Bruno Kessler (FBK) foundry in Trento, Italy.