A High Performance Direct Electron Imager

透射电子显微镜（TEM）的发展在过去几年中取得了巨大的进步，这些仪器现在在世界各地的实验室中常规使用，以超过100 pm的分辨率从许多材料中获得结构数据。然而，对于图像、衍射图案和光谱的数字记录至关重要的探测器仍然基于旧技术，这限制了这些仪器的性能（探测器间隙）。基本问题在于基于电荷耦合器件（CCD）的检测器的构造和操作，所述电荷耦合器件类似于用于光学成像的电荷耦合器件。如果直接暴露于电子束，CCD会损坏，并且必须耦合到将电子束转换为光子的闪烁体。然后这些光子被CCD记录下来。EPSRC资助的项目下的先前研究开发了一种全新类型的传感器，可以直接暴露于中等能量电子，作为间接检测的替代方案。该传感器已被证明具有比间接耦合CCD更高的灵敏度（它能够检测单个电子），并具有更高的分辨率。此外，它可以在计数模式下工作，提供无限的动态范围。这些显著改进的特性将通过提供较少噪声的数字图像和光谱来增强TEM的输出，从而使材料能够以较少的辐射暴露进行研究。当TEM用于研究许多现代材料时，这是至关重要的，例如半导体，催化剂和碳基纳米结构，这些材料经常在电子束中受损。这对于对电子极其敏感的生物材料成像也是至关重要的，并且其中增强的灵敏度将具有相当大的益处。我们现在打算通过构建功能性2D成像作为商业原型来开发这种新型1D传感器的商业潜力。这将需要使用我们现有的技术制造大阵列2D传感器，集成合适的读出电子器件以及设计和构建合适的机械/真空接口以形成原型成像系统。然后，我们将利用这一点向投资者展示该技术在生物学和材料科学的一系列应用实例中相对于现有探测器的明显优势。所有这些步骤都已被证明在原始项目中在技术上是可行的，并且是实现传感器商业潜力的重要步骤。

The development of Transmission Electron Microscopes (TEM's) has made tremendous progress in the last few years and these instruments are now routinely used in laboratories across the world to obtain structural data from many materials at resolutions beyond 100pm. However the detectors that are essential for digital recording of images, diffraction patterns and spectra are still based on old technology which limits the performance of these instruments (the detector gap ). The basic problem lies in the construction and operation of detectors which are based on Charge Coupled Devices (CCD's) similar to those used for optical imaging. CCD's are damaged if directly exposed to the electron beam and must be coupled to a scintillator which converts the beam electrons into photons. These photons are then recorded by the CCD. Previous research under an EPSRC funded project has developed an entirely new type of sensor that can be directly exposed to medium energy electrons as an alternative to indirect detection. This sensor has been shown to have a far greater sensitivity than indirectly coupled CCDs (it is capable of detecting single electrons) and has far higher resolution. In addition it can be operated in a counting mode providing an infinite dynamic range. These significantly improved characteristics will enhance the output from TEM's by providing less noisy digital images and spectra enabling materials to be studied with less radiation exposure. This is vitally important when the TEM is used to study many modern materials, such as semiconductors, catalysts and carbon based nanostructures which are often damaged in the electron beam. It will also be critical for imaging biological materials which are extremely electron sensitive and where the enhanced sensitivity will be of considerable benefit. We now intend to develop the commercial potential of this novel the 1D sensor through the construction of a functional 2D imaging as a commercial prototype. This will require fabrication of a large array 2D sensor using our existing technology, the integration of suitable readout electronics and the design and construction of a suitable mechanical / vacuum interface to form a prototype imaging system. We will then use this to demonstrate to investors the clear advantages of this technology over existing detectors in a range of application examples from both biology and materials science. All of these steps have been demonstrated to be technically feasible within the orginal project and are essential steps in realising the commercial potential of the sensor.