Atomic Layer Deposition for Lancaster Quantum Technology Centre Cleanroom

该奖项将用于购买一种先进的材料制造设备，用于一种称为原子层沉积（ALD）的工艺。顾名思义，ALD能够一次沉积一个原子层的材料。ALD薄膜是通过将样品表面暴露于有机气态化学品（称为前体）来生长的，这些化学品含有所选材料所需的元素，并与表面反应，使得仅沉积一层原子。一个非常常见的例子是绝缘层氧化铝。将具有单个铝原子（三甲基铝）的有机分子引入真空室中。在等待它与表面反应后，去除多余的气体，然后用水蒸气氧化铝。多次重复此循环可形成具有精确厚度的高质量材料层。此外，由于该过程是由前体气体和样品表面之间的化学反应控制的，而不是视线方法，其中材料以某种方式瞄准样品（如一些其他沉积方法的情况），因此整个表面被均匀地涂覆，而不管其拓扑结构如何。ALD在研究和商业生产中应用非常广泛，特别是在微电子工业中。例如，它用于制造DRAM中存储电荷的电容器和构成计算机处理器的晶体管中的介电层。在兰开斯特，ALD将用于补充和增强兰开斯特量子技术洁净室的现有设备，用于凝聚态和材料物理、材料化学和工程方面的广泛研究计划。这些设备将使至少18名来自化学、工程和物理系的学术人员及其研究助理和研究生受益。它也将提供给来自其他大学和工业界的外部用户。

The award will be used for the acquisition of a piece of advanced materials fabrication equipment for a process called atomic layer deposition (ALD). As the name implies, ALD is capable of depositing materials one atomic layer at a time. ALD films are grown by exposing a sample surface to organic gaseous chemicals (called precursors), that contain the required elements for the material of choice, and react with the surface such that just one layer of atoms is deposited. A very common example is the insulating layer aluminium oxide. Organic molecules with single aluminium atoms (trimethylaluminum) are introduced into a chamber that is under vacuum. After waiting for it to react with the surface, excess gas is removed, and then the aluminium is oxidised, e.g. with water vapour. Repeating this cycle multiple times allows the build-up of layers of very high-quality material of precise thickness. Furthermore, since the process is controlled by the chemical reaction between the precursor gas and the sample surface, rather than a line-of-sight method where the materials are somehow aimed at the sample (as is the case with some other deposition methods), the entire surface is coated uniformly irrespective of its topology. ALD is very widely used in research and commercial production, especially in the microelectronics industry. For example, it is used to make the capacitors that store the charge in DRAM and the dielectric layers in the transistors that make up computer processors. In Lancaster ALD will be used to complement and enhance existing equipment in the Lancaster Quantum Technology cleanroom, for a wide range of research programmes in condensed matter and materials physics, materials chemistry and engineering. The equipment will benefit at least 18 members of academic staff from the Departments of Chemistry, Engineering and Physics, their research assistants and research students. It will also be available to external users from other universities and from industry.