Timing Performances and Radiation Hardness of 3D Diamond Detectors
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2022-08-25 |
| Authors | L. Anderlini, Marco Bellini, V. Cindro, C. Corsi, K. Kanxheri |
| Institutions | University of Siegen, Istituto Nazionale di Fisica Nucleare |
| Analysis | Full AI Review Included |
Technical Documentation: Analysis of 3D Diamond Detectors for High Time Resolution and Radiation Hardness
Section titled âTechnical Documentation: Analysis of 3D Diamond Detectors for High Time Resolution and Radiation HardnessâThis document analyzes the research paper âTiming Performances and Radiation Hardness of 3D Diamond Detectorsâ and outlines how 6CCVDâs advanced MPCVD diamond materials and fabrication capabilities can support and extend this critical research in high-energy physics and extreme environment sensing.
Executive Summary
Section titled âExecutive SummaryâThis research successfully demonstrates the superior performance of 3D electrode architecture fabricated on synthetic CVD diamond, achieving state-of-the-art timing resolution and extreme radiation tolerance.
- Core Achievement: Significant improvement in detector time resolution, moving from an initial 280 ps to a highly competitive 80 ps.
- Material Basis: Sensors were fabricated using both mono-crystalline (SCD) and poly-crystalline (PCD) synthetic Chemical Vapor Deposited (CVD) diamond.
- Architecture Advantage: The 3D electrode design enhances both time resolution and radiation hardness compared to standard planar diamond or silicon detectors.
- Radiation Tolerance: Superior radiation hardness was verified up to an extreme fluence level of 1016 neq (1 MeV)/cm2.
- Fabrication Method: 3D electrodes were created using fast laser modification via multiphoton absorption (50 fs, 800 nm Ti:Sa source).
- Application Relevance: The results are highly relevant for next-generation detectors in future particle accelerators (e.g., Timespot experiment), space, and advanced medical applications requiring high speed and durability.
Technical Specifications
Section titled âTechnical SpecificationsâThe following table summarizes the key quantitative performance metrics and fabrication parameters extracted from the research.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Achieved Time Resolution | 80 | ps | Optimized performance of 3D diamond sensors |
| Initial Time Resolution | 280 | ps | Baseline performance before optimization |
| Target Spatial Resolution | 55 | ”m | Required electrode pitch for pixel sensors |
| Maximum Irradiation Fluence | 1016 | neq (1 MeV)/cm2 | Demonstrated radiation hardness limit |
| Detector Material | SCD / PCD | N/A | Synthetic CVD Diamond |
| Laser Pulse Duration | 50 | fs | Used for 3D electrode fabrication |
| Laser Wavelength | 800 | nm | Ti:Sa source |
| Architecture Type | 3D | N/A | Used to minimize charge collection distance |
Key Methodologies
Section titled âKey MethodologiesâThe experimental success hinges on the precise material selection and advanced laser engineering techniques used to create the 3D electrode structure within the bulk diamond.
- Material Selection: High-purity mono-crystalline (SCD) and poly-crystalline (PCD) synthetic CVD diamond wafers were utilized as the base material.
- 3D Electrode Fabrication: The 3D architecture was created using fast laser modification, leveraging multiphoton absorption to define conductive channels within the insulating diamond bulk.
- Laser Source Parameters: A Ti:Sa source was employed, characterized by a short pulse duration (50 fs) and 800 nm wavelength, ensuring precise material modification.
- Performance Optimization: The time resolution was improved by optimizing the material engineering and fabrication procedure, resulting in the reduction from 280 ps to 80 ps.
- Radiation Testing: Sensors were subjected to neutron irradiation up to 1016 neq (1 MeV)/cm2 to verify the superior radiation hardness of the 3D architecture, confirming that hardness increases with bulk electrode density.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD is uniquely positioned to supply the high-purity CVD diamond materials and custom processing required to replicate, scale, and advance this research into commercial or large-scale scientific deployment.
Applicable Materials
Section titled âApplicable MaterialsâTo achieve the 80 ps timing resolution and extreme radiation hardness demonstrated, the highest quality CVD diamond is essential. 6CCVD recommends the following materials:
- Optical Grade Single Crystal Diamond (SCD): Recommended for achieving the absolute best timing performance (80 ps or better) due to its superior purity, low defect density, and high carrier mobility.
- 6CCVD Capability: SCD wafers available in thicknesses from 0.1 ”m up to 500 ”m, with surface roughness (Ra) < 1 nm.
- High Purity Polycrystalline Diamond (PCD): Ideal for scaling up detector arrays (e.g., the 55 ”m pitch pixel sensors) where large area coverage is required.
- 6CCVD Capability: PCD plates available up to 125 mm in diameter, with thicknesses up to 500 ”m. Polishing available to Ra < 5 nm for inch-size plates.
- Boron-Doped Diamond (BDD): While not used in this specific study, BDD substrates can be provided for researchers exploring integrated conductive layers or alternative electrode fabrication methods.
Customization Potential
Section titled âCustomization PotentialâThe fabrication of 3D diamond detectors requires precise material handling, custom dimensions, and specialized contact deposition. 6CCVD provides end-to-end support for these requirements:
| Research Requirement | 6CCVD Capability | Benefit to Researcher |
|---|---|---|
| Custom Dimensions | Plates/wafers available up to 125 mm (PCD). | Enables scaling from R&D prototypes to full-size detector arrays. |
| Precise Thickness | SCD/PCD thickness control from 0.1 ”m to 500 ”m. | Critical for optimizing charge collection distance in 3D architectures. |
| Electrode Metalization | In-house deposition of Au, Pt, Pd, Ti, W, and Cu. | Allows for custom contact schemes necessary for bonding the 3D pixel array (e.g., Ti/Pt/Au stacks). |
| Surface Quality | Ultra-low roughness polishing (Ra < 1 nm for SCD). | Essential for subsequent lithography and bonding processes required for high-density pixel arrays (55 ”m pitch). |
| Global Logistics | Global shipping via DDU (default) or DDP. | Ensures rapid and reliable delivery of custom materials worldwide. |
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house team of PhD material scientists and engineers specializes in optimizing CVD diamond properties for extreme environments. We offer direct consultation for projects focused on:
- High Energy Physics (HEP): Assisting with material selection and specification for projects similar to the INFN Timespot experiment, focusing on high radiation tolerance and ultra-fast timing.
- Laser Processing Compatibility: Providing diamond substrates optimized for femtosecond laser modification and 3D structuring, ensuring consistent results for electrode formation.
- Detector Design: Consulting on the optimal thickness and purity trade-offs between SCD and PCD for specific timing and spatial resolution requirements.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
High time resolution and extreme radiation hardness are key for detectors to be operated in future particle accelerators and in space or medical applications. With respect to these relevant properties, we report here on performances of pixel sensors prepared on mono- and poly-crystalline synthetic Chemical Vapor Deposited (CVD) diamonds, by fast laser modification via multiphoton absorption from a 50 fs, 800 nm, Ti:Sa source. The research has been carried out in the framework of the Timespot experiment of the Italian National Institute for Nuclear Physics (INFN) aimed to achieve both high spatial resolution (55 ÎŒm pitch) and very high time resolution (tens of picoseconds) with very radiation tolerant detectors. Timespot exploits the recent 3D electrode architecture to enhance both time resolution and radiation hardness with respect to standard planar silicon and diamond detectors. We present here a major step forward in material engineering and fabrication procedure, yielding a time resolution improvement of our devices from the initial 280 ps to the present 80 ps, bringing this figure of merit very close to that allowed by the more mature 3D silicon technology. Recent results will be presented, and strategies for further improvements will be discussed. Since diamond is known to be a very radiation-tolerant material, it is considered very promising for implementing devices planned for very fast response and radiation hardness. We present results on a thorough study of polycrystalline and monocrystalline diamond sensors irradiated up to a fluence level of 1016 neq (1 MeV)/cm2. The superior radiation hardness of the 3D architecture is demonstrated with respect to the planar detectors. We have also verified that the radiation hardness increases with increasing bulk electrode density. The results are discussed and compared with other radiation hardness studies carried out on 3D diamond sensors.