Novel Sensors for Particle Tracking - a Contribution to the Snowmassn Community Planning Exercise of 2021

At a Glance

Metadata	Details
Publication Date	2022-02-23
Journal	arXiv (Cornell University)
Authors	S. Spagnolo, S. Kim, J. Metcalfe, A. Sumant
Institutions	Commissariat à l’Énergie Atomique et aux Énergies Alternatives, Centre de Nanosciences et de Nanotechnologies
Citations	1
Analysis	Full AI Review Included

Executive Summary

This paper details five contemporary sensor technologies aimed at revolutionizing particle tracking for future High Energy Physics (HEP) applications, focusing on extreme radiation environments and high precision.

3D Silicon Sensors: Decouple depletion depth from sensor thickness, achieving radiation tolerance up to 10¹⁶ neq/cm² currently, with a goal of 10¹⁸ neq/cm² and timing resolution near 10 ps for HL-LHC and FCC-hh.
3D Diamond Detectors: Utilize column-like electrodes fabricated via femtosecond laser microstructuring to reduce charge carrier drift distance, targeting radiation immunity beyond 10¹⁷ hadrons/cm².
Submicron Pixels (DoTPiX): Proposed for linear colliders (ILC) vertexing, using a single n-channel MOS transistor architecture with a buried quantum well (Ge on Si) to achieve vertex resolution of 0.5 µm.
Thin Film (TF) Detectors: Offer fully integrated, large-area, low-power, and low-mass solutions, potentially reducing detector cost to less than 1% of current Si-CMOS technology while achieving spatial resolution better than 10 µm.
Scintillating Quantum Dots (QDs) in GaAs: Achieve ultra-fast timing (38 ps resolution measured) and high light yield by embedding InAs QDs in a GaAs matrix, suitable for future collider experiments requiring timing resolution better than 10 ps.

Technical Specifications

Parameter	Value	Unit	Context
Si 3D Radiation Tolerance (Current)	10¹⁶	neq/cm²	LHC experiments
Si 3D Radiation Tolerance (HL-LHC Goal)	2.3 x 10¹⁶	neq/cm²	Innermost tracking volume (10 years)
Si 3D Radiation Tolerance (Future Goal)	10¹⁸	neq/cm²	FCC-hh facilities
Si 3D Timing Resolution (Measured)	30 - 180	ps	50 x 50 µm² cell 3D sensors
Si 3D Timing Resolution (Goal)	10	ps	Future 3D silicon technologies
Si 3D Carrier Lifetime (HL-LHC)	0.3	ns	Corresponds to 30 µm mean free path
Diamond 3D Radiation Tolerance (Goal)	> 10¹⁷	hadrons/cm²	Exceeding HL-LHC doses
Diamond 3D Laser Wavelength	800	nm	Femtosecond laser microstructuring
Diamond 3D Column Diameter	2.6	µm	For 50 x 50 µm² cells
Vertex Resolution (DoTPiX Goal)	0.5	µm	Secondary vertex reconstruction (ILC)
DoTPiX Pixel Pitch	Less than 1	µm	Required for trigger-free mode
DoTPiX Active Layer Thickness	Order of 5	µm	Enabling detection of minimum ionizing particles
Thin Film Spatial Resolution	Less than 10	µm	High resolution capability
QD Scintillator Timing Resolution (Measured)	38	ps	Using Am²⁴¹ alpha sources
QD Scintillator Decay Constant	270	ps	Measured at room temperature
QD Scintillator Light Yield (Measured)	1.7 x 10⁴	electrons/MeV	Detected electrons per 1 MeV deposited energy
QD Scintillator Emission Energy	1.1	eV	Infrared photons
QD Scintillator Self-Absorption	~ 1	cm^-1	Low self-absorption in GaAs matrix

Key Methodologies

3D Silicon Sensor Development: Involves TCAD simulations, process optimization, and fabrication of multiple generations of prototypes, followed by characterization before and after irradiation to extreme fluences (up to 10¹⁸ neq/cm²).
Diamond Microstructuring: Utilizes a 130 fs laser (800 nm wavelength) focused to a 2 µm spot to convert bulk diamond into an electrically resistive mixture of carbon phases, creating column-like electrodes. A Spatial Light Modulator (SLM) corrects spherical aberrations during fabrication.
DoTPiX Fabrication (Submicron Pixels): Development of the basic structure using Ultra-High Vacuum/Chemical Vapor Deposition (UHV/CVD) techniques to deposit a thin Germanium (Ge) layer on a silicon substrate, forming the buried quantum well gate.
Thin Film Detector Processing: Employs crystalline growth techniques such as chemical bath deposition and close-space sublimation to layer materials, avoiding traditional silicon fabrication methods (drilling and etching) to achieve low cost and high precision.
Quantum Dot Detector Testing: Involves measuring single-channel performance of InAs QD/GaAs scintillators using Am²⁴¹ alpha sources (5.5 MeV) and fast preamplifiers to determine decay time, rise time, and timing resolution. Monolithic integration of InGaAs photodiodes directly onto the scintillator surface is used for efficient light collection.

Commercial Applications

The advanced sensor technologies developed for extreme HEP environments have direct relevance across several high-tech sectors requiring radiation hardness, high speed, and ultra-high spatial resolution.

Advanced Semiconductor Manufacturing:
- DoTPiX and Thin Film: Techniques like UHV/CVD and thin film deposition for monolithic integration are critical for next-generation CMOS nodes (SOI, FDSOI) and nanowire devices, enabling high-density, low-power electronics.
Medical and Industrial Imaging:
- Quantum Dot Scintillators: The ultra-fast timing (38 ps) and high light yield are highly valuable for Positron Emission Tomography (PET) scanners, improving coincidence timing resolution and image quality.
Space and Defense Electronics:
- 3D Silicon and Diamond Sensors: The inherent radiation hardness (up to 10¹⁸ neq/cm²) makes these materials ideal for electronics and detectors operating in high-radiation environments, such as satellites, deep-space probes, and nuclear facilities.
High-Speed Data Acquisition:
- 3D Silicon Sensors: The focus on achieving 10 ps timing resolution is essential for high-speed data processing and synchronization in large-scale computing and communication infrastructure.
Non-Destructive Testing (NDT) and Security:
- Thin Film Detectors: Large-area, low-cost, flexible thin film arrays can be used for high-resolution X-ray and neutron detection in industrial inspection and security screening systems.

View Original Abstract

Five contemporary technologies are discussed in the context of their\npotential roles in particle tracking for future high energy physics\napplications. These include sensors of the 3D configuration, in both diamond\nand silicon, submicron-dimension pixels, thin film detectors, and scintillating\nquantum dots in gallium arsenide. Drivers of the technologies include radiation\nhardness, excellent position, vertex, and timing resolution, simplified\nintegration, and optimized power, cost, and material.\n

Tech Support

Original Source

DOI: https://doi.org/10.48550/arxiv.2202.11828