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颗粒超栅极场效应晶体管的结构开发室温运行的单光子光电探测器。这种光电探测器将使用入射的光子作为切换阀，控制流经晶体管的电流。光吸收纳米粒子将被夹在两个栅介质层之间，以调节晶体管的源漏输出电流。第二层介电层的厚度将被控制得非常小，以便纳米粒子中的光生电子可以通过电子和空穴之间的柱状相互作用引起半导体沟道中空穴输运行为的显著变化。因此，纳米粒子中的一个被吸收的光子可以在晶体管中引起很大的输出电流变化，这将在单光子检测应用中实现巨大的表观增益。通过优化半导体沟道材料、器件结构参数以及缩小晶体管探测器尺寸以实现单光子探测，将提高现有光电探测器的灵敏度。如果成功，该项目将产生新一代低成本、一次性、非致冷单光子探测器，其性能将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。超门探测机制和器件结构还将为从近红外到紫外线的宽光谱极弱辐射以及X射线等高能辐射的单光子探测建立平台。这种类型的光电探测器在传感器阵列中的应用将使分辨率更高的图像成为可能，因为每个像素的填充因子都增加了。这种高灵敏度的光电探测器在医疗设备中的应用，如计算机断层扫描仪，将减少患者受到的辐射剂量。

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.