AMORPHOUS CHALCOGENIDE-BASED OPTOELECTRONIC PLATFORM FOR NEXT-GENERATION OPTOELECTRONIC TECHNOLOGIES

材料的发现、开发和修改一直是发展我们生活的世界的关键因素。对表现出电学或光学性质的材料的研究在实现所有现代技术，特别是电子、计算和通信方面发挥了重要作用。随着这些技术的发展，现有材料也得到了改进，并接近其技术上可行的极限。这方面的一个例子是基于硅(Si)的微电子技术的进步，这导致与处理能力有关的速度变得至关重要，用于实现这一点的微电子设备的尺寸减小。随着规模的减小，这种方法最终会受到限制；因此，必须寻求替代方法。众所周知，光通信和数据传输要快得多，因为信息可以以光速移动。然而，每当它与电子设备交互时，例如当宽带光纤连接到计算机时，数据传输和处理必须减慢到微电子处理器的速度。因此，有一种强烈的愿望和令人信服的论点，即开发一种光电子技术，它是光学和电子系统的混合体，但没有这两种当前独立工作的技术所造成的当前限制。这项提议将寻求将现代微电子学的基础--离子注入--最先进的材料改性工具之一应用到一类显示出实现未来光电子技术的独特潜力的材料上。这些被称为硫系化合物的材料已经被广泛应用于光伏(太阳能电池)、存储器(如DVD)和先进光学设备(如激光)。然而，目前它们只被用作电子材料或光学材料，每种材料都使用不同类型的硫化物。它们的性能允许在这些单独的应用类型中使用，这给了它们开发的潜力，使得一种材料的优良光学性能可以与另一种材料的优良电子性能相结合，反之亦然。尚未做到这一点的原因之一是，事实证明，在材料制备过程中修改它们的电子性质极其困难，这通常涉及高温熔化。添加到材料中的任何东西，称为掺杂，在这些条件下都是无效的，因为材料在熔化时能够重新排序，以抵消预期的效果。在这项工作计划中，我们将通过在硫化物材料中引入低于其熔体温度的掺杂剂来修改性能，从而不允许材料重新排序。这将通过离子注入进行，它允许精确控制引入的杂质类型。作为这项工作的结果，我们将第一次了解如何以受控的方式对这些独特的材料进行改性。然后，我们将利用这一点来开发更好的材料电子和光学性质来源的模型，这将使我们能够开发优化的材料。我们还将开发原型设备，引领真正的光电子技术的发展。该计划将使英国成为这一领域的领导者，从而直接促进知识经济的持续增长。我们将培训下一代科学家和工程师使用最先进的技术，以确保英国保持这方面所需的专业知识基础，旨在确保这项工作的影响最大化并在可能的情况下加速，并将结果广泛传达给包括这项研究的所有利益相关者。

Materials discovery, development and modification has been a key factor in developing the world we live in. The study of materials which exhibit electrical or optical properties has played a major role in enabling all of modern technology and in particular electronics, computing and communications. As these technologies have been developed existing materials have also been modified and pushed close to their limits of what is technical feasible. An example of this is the advances made in silicon (Si) based microelectronics which has led to speed, which relates to power of processing, becoming critical, with a reduction in the size of the microelectronics used to achieve this. This approach is ultimately limited as sizes reduce; thus alternative methods must be sought. Optical communication and data transfer is widely known as being much quicker as information can be moved at the speed of light. However, whenever it interacts with electronics, such as when broadband optical fibre is connected to a computer the data transfer and processing must slow down to the speed of the microelectronic processors. There is a strong desire and compelling argument therefore to develop an 'optoelectronic' technology which is a hybrid of the optical and electronic systems but without the current limitations imposed by the two current technologies working independently. This proposal will seek to apply one of the most developed materials modification tools that is fundamental to modern microelectronics, ion-implantation, to a class of materials that show unique potential for enabling future optoelectronic technologies. These materials, known as chalcogenides, are already widely used in applications such as photovoltaics (solar cells), memory (e.g. DVDs), and advanced optical devices (e.g. lasers). Currently however they are used solely as either electronic materials or optical materials, with different types of chalcogenides used for each. Their properties that allow use in these separate application types gives them the potential to be developed so that the excellent optical properties of one material can be combined with the excellent electronic properties of another and vice versa. One of the reasons that this has yet to be done is that it has proved to be extremely difficult to modify their electronic properties during the material preparation which typically involves melting at high temperatures. Anything that is added to the materials, referred to as doping, is ineffective under these conditions due to the ability of the material to reorder itself whilst melted to cancel out the desired effect. In this programme of work, we will modify the properties by introducing dopants into the chalcogenide materials below their melt temperature, thus not allowing the material to reorder. This will be undertaken using ion-implantation which allows precise control of the type of impurity introduced. As a result of this work, we will develop for the first time an understanding of how these unique materials can be modified in a controlled way. We will then use this to develop better models of the origin of the materials' electronic and optical properties which will allow us to develop optimised materials. We will also develop prototype devices that will lead the way to the development of a truly optoelectronic technology. This programme will establish the UK as leaders in this field and therefore directly contribute to the continuing growth of the knowledge economy. We will train the next generation of scientists and engineers in state-of-the-art techniques to ensure that the UK maintains the expertise base required for this, aim to ensure the impact of this work is maximised and accelerated where possible, and communicate the results widely including to all stakeholders in this research.