Development of micro-thermal dividers for hybrid pixel detectors coupling cryogenic HPGe sensors and room temperature ASICs.

开发用于耦合低温 HPGe 传感器和室温 ASIC 的混合像素探测器的微热分配器。

• 批准号: EP/X017494/1
• 负责人: Marcello Borri
• 金额: $ 24.99万
• 依托单位: Science and Technology Facilities Council
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX017494%2F1
• 关键词: Development; micro; thermal; dividers; hybrid

This project is proposing a new, unproven and disruptive technology to enable the application of High Purity germanium (HPGe) sensors with existing room temperature Application Specific Integrated Circuits (ASICs) in hybrid pixel detectors. It is proposed to design and test a micro-thermal divider translating the physics requirements set by the Fourier's Law of heat conduction, into an engineered solution exploiting the capabilities offered by micro-fabrication and micro-machining processes, and by micro-electronics interconnection techniques. The micro-thermal divider will control a challenging delta T of ~130deg C over few 100's um. The hybrid pixel detectors prototyped in this project will target mainly applications in photon-science. Here, hybrid pixel detectors provide high performance solutions for X-ray detection by combining direct photon detection, small pixel size, fast readout and sophisticated signal processing circuitry in each pixel. For X-ray detection above 20 keV, high-Z sensors different than silicon are required to achieve high quantum efficiency, but many high-Z materials such as GaAs, CdTe and CdZnTe often suffer from unfavourable material properties or nonuniformities. Remarkably, HPGe crystals provide a unique combination of favourable crystal properties and material purity that translates into a high, uniform detection efficiency and an excellent energy resolution, over a large area (wafers ~90mm dia.). The deployment of HPGe sensors in hybrid pixel detectors is currently limited by the cryogenic requirements of the sensors, which is usually linked to the development of cryogenic ASICs. These are niche, complex and costly developments. Instead, we propose a shift of paradigm in the existing thought by studying the effectiveness of micro-technologies to replace the need of cryogenic ASICs for high-energy radiation detection instrumentation. To achieve this, a micro-thermal divider will be inserted between the sensor and the ASIC. It will insulate the sensor from the heat generated by the ASIC, and it will provide direct cooling underneath the sensor.The high-risk and speculative aspect of the project is related to managing a high temperature gradient (~130deg C) over a short distance (100's um), while maintaining an excellent electrical performance and mechanical stability of the device. The ambition of this bid is to build a functional prototype demonstrating the feasibility of the technology (proof of concept), and generating foundation work for the next iteration, where a fully engineered device will be built.The main aim of the project is to position the UK in a leadership role to build the next generation of hybrid pixel detectors for flagship synchrotron and free electron laser experiments. We want to develop an innovative technique to operate HPGe sensors with room temperature ASICs. High-end applications like nuclear medical imaging applications (detecting gamma-rays) and X-rays spectral molecular imaging would also be beneficiaries of this technological progress, which has the potential to improve the quality of diagnostics in healthcare. There is an energy saving aspect related to this proposed solution. The operating temperature of a room temperature ASIC would require less cooling power than an equivalent cryogenic ASIC. This would contribute to reduce the carbon footprint while developing cutting edge instrumentation based on HPGe sensors. The analogy of satellite operations with in-vacuum thermal management/energy efficiency via micro thermal-dividers could lead to more efficient thermal control systems for space instrumentation. Finally, R&D on a micro thermal-divider has synergies with the field of quantum computing. Here, our approach could be used to develop new packaging solutions for the quantum-to-classical interface in a cryogenic environment with multiple temperature stages. For instance, this could benefit quantum computers based on superconducting qubits.

该项目提出了一种未经证实的颠覆性新技术，可将高纯锗 (HPGe) 传感器与现有室温专用集成电路 (ASIC) 一起应用于混合像素探测器。建议设计和测试微热分配器，将傅立叶热传导定律设定的物理要求转化为利用微制造和微加工工艺以及微电子互连技术提供的功能的工程解决方案。微型热分配器将在几百微米内控制约 130 摄氏度的挑战性温差。该项目中原型的混合像素探测器将主要针对光子科学中的应用。在这里，混合像素探测器通过在每个像素中结合直接光子探测、小像素尺寸、快速读出和复杂的信号处理电路，为 X 射线探测提供高性能解决方案。对于 20 keV 以上的 X 射线检测，需要使用不同于硅的高 Z 传感器来实现高量子效率，但许多高 Z 材料（例如 GaAs、CdTe 和 CdZnTe）往往会遇到不利的材料特性或不均匀性。值得注意的是，HPGe 晶体提供了有利的晶体特性和材料纯度的独特组合，可在大面积（晶圆直径约 90 毫米）上转化为高、均匀的检测效率和出色的能量分辨率。 HPGe 传感器在混合像素探测器中的部署目前受到传感器低温要求的限制，这通常与低温 ASIC 的开发相关。这些都是利基、复杂且成本高昂的开发项目。相反，我们提出通过研究微技术的有效性来改变现有思想的范式，以取代高能辐射检测仪器对低温 ASIC 的需求。为了实现这一点，将在传感器和 ASIC 之间插入一个微型热分配器。它将传感器与 ASIC 产生的热量隔离，并将在传感器下方提供直接冷却。该项目的高风险和投机性方面与短距离管理高温度梯度（约 130 摄氏度）有关(100's um)，同时保持器件优异的电气性能和机械稳定性。本次投标的目标是构建一个功能原型，展示该技术的可行性（概念验证），并为下一次迭代提供基础工作，其中将构建完全工程化的设备。该项目的主要目标是定位英国在为旗舰同步加速器和自由电子激光实验构建下一代混合像素探测器方面发挥了领导作用。我们希望开发一种创新技术，通过室温 ASIC 操作 HPGe 传感器。核医学成像应用（检测伽马射线）和 X 射线光谱分子成像等高端应用也将受益于这一技术进步，这有可能提高医疗保健诊断的质量。该解决方案涉及节能方面。室温 ASIC 的工作温度需要比同等低温 ASIC 更少的冷却功率。这将有助于减少碳足迹，同时开发基于 HPGe 传感器的尖端仪器。通过微型热分配器将卫星运行与真空热管理/能源效率进行类比，可以为空间仪器带来更高效的热控制系统。最后，微型热分配器的研发与量子计算领域具有协同效应。在这里，我们的方法可用于为具有多个温度阶段的低温环境中的量子经典界面开发新的封装解决方案。例如，这可能有利于基于超导量子位的量子计算机。