Sensitvity leap for far ultraviolet single photon avalanche diodes

远紫外单光子雪崩二极管的灵敏度飞跃

• 批准号: RGPIN-2017-06409
• 负责人: Charlebois, Serge
• 金额: $ 1.75万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=647229
• 关键词: Sensitvity; leap; far; ultraviolet; single

The 2015 Nobel prize in physics was awarded for the discovery that neutrinos have mass. But their absolute mass is still unknown. Are neutrinos Majorana fermions, a theoretical particle type which is simultaneously matter and anti-matter? The field of astroparticle physics aims to answer these key questions in the coming years. The required experiments involve huge volumes of liquid Xe or Ar at cryogenic temperatures and 4 to 100 m2 of ultraviolet sensitive photodetectors.***For an instrumentation engineer, this translates into creating a camera that has many m2 of sensitive area to count each of the few ultraviolet photons emitted in all direction by the liquid Xe or Ar scintillation. The technology identified to make this camera is based on Single Photon Avalanche Diodes (SPAD) made of silicon. I led the fabrication of a unique concept of fully digital photon counting called 3DdSiPM that will make scaling up to many m2 possible. A limiting issue for all silicon based SPAD detectors is the sensitivity of the photodiodes themselves in the VUV range (100-200 nm).***The objective of my research program is to boost the sensitivity of SPAD detectors by at least a factor of three. To do so, special epitaxial techniques suited for mass production will be used to engineer the conduction band profile of the SPAD. This approach has allowed CCDs to perform very well in the VUV range. Antireflection coating of the surface of the SPAD will also be fabricated using the Atomic Layer Deposition technique. This technique can build the extremely thin layers needed to construct the antireflection multilayer structure for very short VUV wavelengths.***Tripling the sensitivity of SPAD based detectors would be a game changer in many astroparticle physics experiments. It will also stimulate the field of medical imaging by enabling new techniques called Time-of-Flight Position-Emission-Tomography (ToF-PET) to make exams faster and the radiation dose lower. **

2015年诺贝尔物理学奖是因为发现中微子有质量而颁发的。但它们的绝对质量仍然未知。中微子是马约拉纳费米子，一种理论上同时是物质和反物质的粒子类型吗？天体粒子物理学领域的目标是在未来几年内回答这些关键问题。所需的实验涉及大量低温下的液态氘或氩和4至100平方米的紫外敏感光电探测器。对于仪器工程师来说，这意味着创建一个具有许多平方米敏感区域的相机，以计数由液体闪烁或Ar闪烁在所有方向上发射的少量紫外光子中的每一个。该相机的制造技术基于硅制成的单光子雪崩二极管（SPAD）。我领导了一个独特的全数字光子计数概念的制造，称为3DdSiPM，这将使扩大到许多平方米成为可能。所有硅基SPAD探测器的一个限制性问题是光电二极管本身在VUV范围（100-200 nm）内的灵敏度。我的研究计划的目标是将SPAD探测器的灵敏度提高至少三倍。为此，将使用适合大规模生产的特殊外延技术来设计SPAD的导带分布。这种方法使CCD在VUV范围内表现非常好。SPAD表面的减反射涂层也将使用原子层沉积技术制造。这种技术可以构建极薄的层，以构建用于非常短的VUV波长的MEMS多层结构。将SPAD探测器的灵敏度提高三倍将改变许多天体粒子物理实验的游戏规则。它还将通过启用称为飞行时间位置发射断层扫描（ToF-PET）的新技术来刺激医学成像领域，使检查更快，辐射剂量更低。**