Electron-beam Deposition System for Nanofabrication Processes

微纳米制造技术涉及多个复杂的步骤，以努力制造高度可重复性和高质量的微型化结构和器件。在制造功能器件的关键步骤中，金属薄膜(金、银、铬和铂)的沉积是任何微米和纳米级器件制造的核心。电子束(电子束)沉积系统是一种在高真空环境下产生电子束并聚焦到金属靶上的装置。然后，金属原子被电子通量喷射出来，沉积到目标上，在那里产生微结构和纳米结构。电子束沉积提供了高度可控的沉积速度，从而获得了均匀和原始的金属表面。这项技术允许人们在一个4英寸的晶片表面构思和制造一系列微米和纳米特征。在典型的多步骤制造工艺中，电子束沉积系统在整个序列中重复使用。例如，在沉积金层之前，在半导体表面上沉积由钛或铬组成的粘附层。在西方纳米加工设施中制备的器件通常具有3层或更多层。层的厚度取决于层在最终器件中的作用，从几纳米到数百纳米不等。 因此，高质量的电子束沉积系统是任何先进制造程序在纳米级取得成功的关键。西方纳米加工设施与4英寸晶片完全兼容，希望获得能够处理这些晶片的电子束沉积系统。目前在西方纳米加工设施中运行的系统是一个开放的用户设备，是在20世纪80年代的S时代生产的。它是纳米加工设施中最繁忙的机器之一。然而，按照今天的标准，它的电子、抽水和安全操作都已经过时，这强调了迫切需要更换。此外，一种新的仪器将极大地提高每一种制备的金属层的均匀性和纯度，这为我们的研究人员提供了在纳米级探索新方法和新器件的先进能力。

Micro and Nano-fabrication technologies involve multiple complex steps in an effort to fabricate miniaturized structures and devices with a high degree of reproducibility and quality. Among the steps that are essential to make a functional device, deposition of metallic thin films (gold, silver, chromium, and platinum) are central to any fabrication of micro- and nano-scale devices. An electron beam (e-beam) deposition system is an apparatus where an electron beam is produced under high vacuum environment and focused onto a metal target. The metal atoms are then ejected by the electron flux and are deposited onto a target where the micro- and nanostructures are produced. Deposition by electron beam provides a highly-controlled rate of deposition resulting in a uniform and pristine metal surface. This technology allows one to conceive and fabricate a collection of micro- and nano-features over the surface of a single 4-inch wafer. In a typical multi-step fabrication process, the electron beam deposition system is used repeatedly throughout the sequence. For example, an adhesion layer comprised of titanium or chromium is deposited onto a semiconductor surface prior to deposition of a gold layer. Devices prepared in the Western Nanofabrication Facility typically have 3 or more layers. Layer thickness depends on the role of the layer in the final device and can vary from several nanometers to hundreds of nanometers. A high-quality e-beam deposition system is therefore the key to the success of any advanced fabrication procedure at the nanoscale. The Western Nanofabrication Facility being fully compatible with 4-inch wafers, wishes to acquire an e-beam deposition system capable of processing these wafers. The present system operating in the Western Nanofabrication Facility is an open user apparatus and was produced in the 1980’s. It is one of the busiest machines in the Nanofabrication Facility. However, its electronic, pumping and safety operation are obsolete by today’s standards, which emphasizes the urgent need for a replacement. Furthermore, a new instrument would greatly improve the uniformity and purity of each prepared metal layer, which provides our researchers with advanced capabilities to explore new methods and devices at the nano-scale.