Machining metre-sized gratings with nanometre accuracy

这项提议的研究旨在开发一种新的能力来制造几米大小的结构，但精确到纳米水平。这利用了精密制造的新范例，它将结合两种不同的方法。第一种是利用材料的可重复和/或严格周期性的原子或分子尺度特性来制造在小尺度上精确的结构。第二种是利用高精度干涉测量技术，在远距离上精确定位“书写”头。通过结合这些方法，我们的目标是使用精确的“定位头”在米大小的区域上“定位”小规模结构，从而保证更大规模的订单。在发展这种新方法的第一步，我们将制造一些中等尺寸（直径150毫米）的梯级衍射光栅。这些由反射表面上的规则和精确的微型凹槽组成，并用于光谱学和其他测量和分析科学。为了做到这一点，我们将设计并制造一种新的“控制引擎”，它将精确地定位光学激光头，精确到几千分之一根头发的宽度，在硅衬底表面之上。激光头将被精确地引导在硅表面上，以便设置通过随后蚀刻硅制成的凹槽的位置。测试时，光栅的光学性能将用于改进写入头的主动控制和位置，并验证如何成功地在越来越大的区域保持位置精度。从长远来看，我们的目标是开发一种定位精确书写头的系统，以提供一种更通用的制造技术，从而允许在一系列表面上以前所未有的精度书写任意二维图案。最终的目标将是制造出一台能够在一米大小的区域上“书写”纳米精度的二维图案的机器。

The proposed research aims at developing a new capability to manufacture structures which are metres in size, but accurate at the nanometre level. This makes use of a new paradigm for precision manufacturing which will combine two separate approaches. The first exploits the repeatable and/or strictly periodic atomic or molecular scale properties of materials to fabricate structures which are accurate on small scales. The second exploits high precision interferometric metrology to position a "writing" head accurately and precisely over large distances. By combining these methods, we aim to "position" the small-scale structures over metre-sized areas using an accurate "location head", thereby guaranteeing much larger-scale order. In this first step towards the development of this novel approach, we will fabricate a number of moderate sized (150 mm diameter) echelle diffraction gratings. These consist of regular and precise sets of miniature grooves on a reflecting surface, and are used in spectroscopy and other measurement and analysis sciences. To do this we will design and build a novel "ruling engine" that will position an optical laser head precisely and accurately, to a few thousandths of a hair's breadth, above the surface of a silicon substrate. The laser head will be precisely guided over the silicon surface so as to set the locations of grooves made by subsequently etching the silicon. When tested, the optical performance of the gratings will be used to refine the active control and position of the writing head, and to validate how successfully positional accuracy can be maintained over larger and larger areas. In the longer term, we aim to develop the system which positions the precision writing head to deliver a more general manufacturing technology so as to allow the writing of arbitrary 2-dimensional patterns on a range of surfaces with unprecedented accuracy. The eventual goal will be to produced a machine capable of "writing" nanometre-accurate 2-d patterns over metre-sized areas.