SBIR PHASE I: Microporous Alumina Microchannel Plates

微通道板(MCP)在科学、医学和工业中的高增益成像和检测应用中是必不可少的。它们对入射的带电粒子和UV/x射线粒子具有优异的时间分辨率，工作在强磁场中，对于科学仪器中的许多粒子检测应用是必不可少的，例如闪烁纤维粒子跟踪器。然而，大多数现有的MCP都是由活性玻璃制成的，并且随着从MCP收集的单位面积累积电荷的增加，MCP的增益迅速下降。此外，MCP价格昂贵，可在有限的区域内使用，具有显著的空间不均匀性，并且容易造成辐射损伤。我们建议通过使用阳极化铝板作为MCP的基础来克服其中的许多困难。当在受控阳极氧化下形成时，非晶态氧化铝包含开放的、密集堆积的、垂直于表面取向的微孔，其长径比适合于微通道增益。纯氧化铝具有足够的二次发射增益，因此孔可以作为增益通道，而不会被激活或污染材料。我们预计，这种陶瓷材料将具有比玻璃MCP更好的稳定性和寿命性能，成本非常低，具有大规模MCP区域的潜力。微孔MCP基质比现有的MCP具有更好的空间分辨率和空间均匀性，具有更高的抗辐射能力。增益稳定性和长寿命将使快速、紧凑的MCP技术在各种真空电子放大应用中得到更广泛的应用。在第一阶段，我们提出了通过阳极氧化来制备原型的非晶氧化铝MCP，并测量了其增益、增益稳定性和空间特性。如果成功，将产生比目前MCP更长使用寿命的微/纳米通道板(M/NCP)，并可实现超快、栅极、致密、高磁场、耐辐射MCP光电倍增管(PMT)；(2)具有亚微米空间分辨率的长寿命图像增强器/转换器；(3)平板真空荧光粉显示器；(4)高增益和亚微米空间分辨率的带电粒子/X射线成像探测器。

Microchannel plates (MCP) are essential for high gain imaging and detection applications in science, medicine, and industry. They have superior temporal resolution for incident charged and UV/x-ray particles, operate in high magnetic fields, and are essential for many particle detection applications in scientific instrumentation, such as scintillating fiber particle trackers. However, most existing MCP are fabricated from activated glass and suffer from a gain that falls rapidly with the cumulative charge per area collected from the MCP. Furthermore, MCP are expensive, available in limited areas, have significant spatial non-uniformities, and radiation damage readily. We propose to overcome many of these difficulties by using anodized aluminum plates as the basis of an MCP. When formed under controlled anodization, amorphous alumina contains open, densely packed, straight micropores, oriented perpendicular to the surface, with a length to diameter ratio appropriate for microchannel gain. Pure alumina has a sufficient secondary emission gain so that the pores can serve as gain channels, without activation, or contaminating materials. We anticipate that this ceramic material will have superior stability and lifetime properties to those of glass MCP, at very low cost, with the potential of large MCP areas. The microporous MCP matrix could result in much better spatial resolution and spatial uniformity than existing MCP, with high radiation resistance. The gain stability and long life will enable the fast, compact MCP technology to be used much more widely in a large variety of vacuum electronics amplification applications. In Phase I, we propose to fabricate prototype amorphous alumina MCP's by anodization, and measure gain, gain stability and spatial properties. If successful, micro/nanochannel plates (M/NCP) with a much longer operational life compared with current MCP would result, and could enable ultrafast, gated, compact, high magnetic field, radiation-hard MCP photomultipliers (PMT); (2) long lived image intensifiers/ converters with sub-micron spatial resolution; (3) flat panel vacuum phospher displays; (4) imaging charged particle/x-ray detectors with high gain and sub-micron spatial resolution.