Room-temperature Operation Single-Photon Detectors Based on Nanoparticle Super-gated Organic Field Effect Transistors

该奖项的目标是利用纳米粒子超栅有机场效应晶体管的结构开发室温操作的单光子光电探测器。这种光电探测器将使用入射光子作为开关阀来控制流经晶体管的电流。光吸收纳米颗粒将夹在两个栅极介电层之间，以调节晶体管的源极-漏极输出电流。第二介电层的厚度将被控制为非常小，使得纳米颗粒中的光生电子可以通过电子和空穴之间的库仑相互作用引起半导体沟道中的空穴传输行为的显著变化。因此，纳米颗粒中的一个吸收光子可以引起晶体管中的大的输出电流变化，这将实现用于单光子检测应用的巨大表观增益。通过优化半导体沟道材料、器件结构参数，可以提高现有光电探测器的灵敏度，并且可以缩小晶体管探测器的尺寸，实现单光子探测。如果成功，该项目将产生新一代低成本，一次性，非制冷单光子探测器，其性能超过传统的单光子探测器，如光电倍增管或雪崩光电二极管。超选通探测机制和器件结构还将建立从近红外到紫外的宽光谱的非常弱的辐射以及诸如X射线的高能辐射的单光子探测的平台。这种类型的光电探测器在传感器阵列中的应用将使更高的分辨率的图像，因为每个像素的填充因子增加。这种高灵敏度光电探测器在诸如计算机断层扫描仪的医疗设备中的应用将减少暴露于患者的辐射剂量。

The goal of this award is to develop room-temperature operation single-photon photodetectors utilizing a structure of nanoparticle super-gated organic field effect transistors. Such photodetectors will use the incident photons as a switching valve to control the current flowing through the transistors. Light absorbing nanoparticles will be sandwiched between two gate dielectric layers to tune the source-drain output current of the transistors. The thickness of a second dielectric layer will be controlled to be very small so that photo-generated electrons in the nanoparticles can cause a dramatic variation of the hole transport behavior in the semiconductor channel by the columbic interaction between the electrons and holes. Therefore, one absorbed photon in the nanoparticles can cause a large output current variation in the transistor, which will realize huge apparent gain for single photon detection applications. The sensitivity of present photodectors will be improved with optimized semiconductor channel materials, device structure parameters, and the size of the transistor detector will be scaled down for single photon detection. If successful, this project will yield a new generation of low cost, disposable, uncooled single-photon detectors with unprecedented performance over traditional single photon detectors, such as photomultiplier tubes or avalanche photodiodes. The super-gating detection mechanism and device structure will also establish the platform for single photon detection of very weak radiation from a broad spectrum from near infrared to ultraviolet as well as high energy radiation such as X-ray. The application of this type of photodetector in sensor array will enable higher resolution images because of the increased fill factor of each pixel. The application of such high sensitivity photodetectors in medical devices, such as computerized tomography scanners, would reduce the radiation dose exposed to the patient.