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射线剂量在这些技术中越来越受到关注。剂量的减少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，与传统的硅光探测器相比，其响应率提高了100倍。与标准闪烁体晶体相结合，黑硅光探测器提供了一种有前途的新型传感器技术，可以通过提高信号链内的量子效率来减少患者的剂量。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。黑硅是在可控的六氟化硫气氛下，用飞秒激光对硅片进行加工而形成的。值得注意的是，由黑硅制成的原型器件表现出光导增益特性，每吸收1个光子产生多达100个电子。这项工作的目标是开发优化的黑硅光探测器，提高对工业标准x射线闪烁晶体发射的蓝色光的灵敏度。有了更高的光子灵敏度，进行同样的测量所需的x射线就更少了，从而降低了病人的剂量。

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.