Black Silicon Photodiodes for Enhanced Digital Radiography Detectors

描述（由申请人提供）：随着CT和PET等先进医学成像技术越来越多地应用于更广泛的医学问题，X射线剂量越来越受到关注。剂量降低只能通过提高探测器系统的灵敏度来实现。黑硅是一种新型的光学探测器材料，其响应度比传统的硅光电探测器提高了100倍。黑硅光电探测器与标准闪烁体晶体相结合，提供了一种有前途的新传感器技术，可以通过提高信号链内的量子效率来减少患者剂量。为了实现这一愿景，有必要开发集成黑硅脉冲激光工艺的光电二极管器件。黑硅是在受控的六氟化硫气氛中通过飞秒激光加工硅片形成的。值得注意的是，由黑硅制造的原型器件表现出光电导增益特性，每吸收1个光子就能产生多达100个电子。这项工作的目的是开发优化的黑硅光电探测器，提高对蓝色光的灵敏度，其中工业标准的X射线闪烁体晶体发射。光子灵敏度越高，进行相同测量所需的X射线就越少，从而降低了患者剂量。 公共卫生相关性：这项工作的成果将是一个更高的灵敏度探测器，当集成到先进的射线照相成像系统将提高成像性能，降低整体系统成本。提高成像性能可以减少患者的X射线剂量，或者在相同剂量水平下提高图像保真度和分辨率。

DESCRIPTION (provided by applicant): X-ray dose is a growing concern in advanced medical imaging technologies like CT and PET as these techniques are increasingly applied to a broader set of medical problems. Dose reduction can only be achieved by increasing the sensitivity of the detector system. Black Silicon is a novel optical detector material with a 100x responsivity enhancement over conventional silicon photo detectors. Coupled with standard scintillator crystals, Black Silicon photo detectors provide a promising new sensor technology that can reduce patient dose by improving the quantum efficiency within the signal chain. To realize this vision it will be necessary to develop photodiode devices that integrate the Black Silicon pulsed laser process. Black Silicon is formed by femtosecond laser processing of silicon wafers in a controlled sulfur hexafluoride atmosphere. Remarkably, prototype devices fabricated from Black Silicon exhibit photoconductive gain properties, producing as much as 100 electrons for every 1 photon absorbed. It is the objective of this work to develop optimized Black Silicon photo detectors with enhanced sensitivity to blue colored light, where industry standard x-ray scintillator crystals emit. With higher photon sensitivity, fewer x-rays are required to make the same measurement, thereby lowering the patient dose. PUBLIC HEALTH RELEVANCE: The outcome of this work will be a much higher sensitivity detector that when integrated into advanced radiographic imaging systems will improve imaging performance and reduce overall system cost. Improving the imaging performance can lead to reduced x-ray dose to the patient or improved the image fidelity and resolution at equal dose levels.