Chemical Routes to the Growth of Crystalline Oxides Directly on Germanium for Applications in Future Generation Microelectronic Devices

目前，为微电子器件供电的大多数晶体管是基于硅的。虽然近年来硅基微电子器件的速度有了显著提高，但硅基芯片的工作速度受到材料本身的限制，为了制造更快的器件，需要一种新的半导体材料。锗就是这样一种有前途的材料，可以制造更快的计算机芯片。制造晶体管的一个关键挑战是需要良好的电半导体和与该半导体兼容的良好绝缘体。为了使锗基芯片工作，需要良好的电绝缘体。该奖项旨在开发和了解一种与锗兼容的新型电绝缘体，并可用于制造锗基微电子产品。这项研究的更广泛影响将是继续将晶体管缩小到更小的尺寸，这将为微电子设备提供更快的计算机处理器速度，更低的功耗和更高的数据存储容量。本研究探讨钙钛矿作为锗晶体管中的电介质氧化物。选择钙钛矿是因为它们能够与锗化学键合并消除影响器件性能的电缺陷。这项工作将探索如何在锗上生长晶体钙钛矿氧化物薄膜，以满足现代微电子器件的许多性能要求。该研究探索了一种全化学生长过程，该过程应该是可扩展的，本质上成本较低，并且基于当前的制造工具基础设施，以促进行业的轻松采用。该研究探索和描述了材料化学和表面化学与生长晶体SrHfO 3和SrZrO 3锗使用原子层沉积工艺。总体目标是理解和描述导致在化学沉积过程中在Ge（001）上形成具有必要的能带偏移和界面陷阱密度的晶体氧化物的过程。该工作的智力价值源于基础研究的特定重点领域，这些领域是：1）阐明Ge（001）氧化物界面处的反应和结构变化，该反应和结构变化为结晶氧化物的形成提供了种子; 2）理解导致结晶膜的钙钛矿层中的结构演变以及结构如何取决于工艺条件;以及3）在场效应晶体管应用中的栅极氧化物的情况下建立结构-性质-功能关系。

Presently, the majority of transistors that power microelectronic devices are based on silicon. While there have been significant increases in speed of silicon-based microelectronic devices in recent years, the speed at which silicon-based chips can operate is limited by the material itself, and in order to make faster devices a new semiconductor material is required. Germanium is one such promising material that can enable manufacturing of faster computer chips. One critical challenge in building transistors is the need for a good electrical semiconductor and a good insulator that is compatible with that semiconductor. To make germanium-based chips work, a good electrical insulator is needed. This award is to develop and understand a new type of electrical insulator that is compatible with germanium and which can allow for manufacturing of germanium-based microelectronics. The broader impact of the research will be in continued scaling of transistors to smaller sizes that will provide faster computer processor speeds, lower power consumption, and higher data storage capacities for microelectronic devices. This research examines perovskites for use as dielectric oxides in germanium transistors. Perovskites are selected for their ability to bond chemically to germanium and eliminate the electrical defects that affect device performance. This work will explore how to grow crystalline perovskite oxide films on germanium that meet the many performance requirements of modern microelectronic devices. The research explores an all-chemical growth process that should be scalable, is inherently less costly, and is based on current manufacturing tool infrastructure to promote easy adoption by industry. The research explores and describes the materials chemistry and the surface chemistry associated with growing crystalline SrHfO3 and SrZrO3 on germanium using atomic layer deposition processes. The overarching objectives are to understand and describe processes that lead to the formation of crystalline oxides on Ge (001) with requisite band offsets and interface trap densities in a chemical deposition process. The intellectual merits of the work stem from the specific focus areas of the fundamental studies which are: 1) elucidating the reactions and structural changes at the Ge (001) oxide interface that seed crystalline oxide formation; 2) understanding the evolution of structure in the perovskite layer leading to a crystalline film and how the structure depends on process conditions; and 3) establishing the structure-property-function relationships in the context of a gate oxide in a field effect transistor application.