Thermal Transport in Diamond Thin Films: Roles of the Nanostructure and Interfaces

派：拉杰·N·辛格，大学。CincinnatiCBET-1227788高性能微处理器和功率半导体器件的散热是微电子行业面临的一个关键挑战。集成电路(IC)散热最有效的方法之一是使用与IC接触的导热系数高的材料。在这种背景下，一种高导热系数的材料，特别是具有最高导热系数的金刚石，在集成电路的热管理方面是很有前途的。具体地说，本研究的目的是合成层状金刚石薄膜，其中一层(纳米金刚石-NCD)将提供光滑的表面以降低界面电阻，而第二层(微晶金刚石-MCD)将产生较高的热导率。该方法将包括使用内部微波等离子体增强化学气相沉积系统分别合成NCD和MCD薄膜以及作为层状NCD/MCD薄膜，并使用定制的调制光热反射系统测量热性能。一种新的纳米晶种方法将被用来降低粗糙度和界面热阻。先进的材料表征技术将被用来识别薄膜中的缺陷，并与声子散射的平均自由程有关，以识别控制层状金刚石薄膜热输运的主要缺陷。据我们所知，这项研究具有重大的意义和革命性，因为这将是第一次全面研究工艺对NCD和层状NCD/MCD薄膜的纳米结构、缺陷和热输运机制的影响。由于热管理在包括光电子、微电子、电力电子和微电子机械系统在内的几个高科技领域发挥着关键作用，因此拟议的研究具有巨大的回报潜力。此外，由于目前的重点是保护我们有限的自然资源用于能源生产，有效的热管理战略将直接节省冷却成本，从而降低能源消耗，并对环境产生显著的积极影响。这项研究的一个重要组成部分将是对学生和博士后进行培训和教育，并通过在期刊上发表文章和在会议上发表演讲来传播研究成果。少数族裔/女性和高中生将通过我们大学的几个项目进行指导和接触研究。通过为教师和学生开设夏令营，计划向高中开展一项重大活动。

PI: Raj N. Singh, Univ. of CincinnatiCBET-1227788 Heat dissipation in high performance microprocessors and power semiconductor devices is a critical challenge facing the microelectronics industry. One of the most effective ways to remove heat from integrated circuits (ICs) is to use materials with high thermal conductivity in contact with ICs. In this context, a high thermal conductivity material, especially diamond with the highest thermal conductivity of any known materials, is promising for thermal management of ICs. In particular, the objective of this research is to synthesize layered thin films of diamond in which one layer (nanocrystalline diamond-NCD) will provide smooth surfaces for lower interface resistance and the second layer (microcrystalline diamond-MCD) will result in high thermal conductivity. The approach will involve the synthesis of NCD and MCD films individually and as layered NCD/MCD films using an in-house microwave plasma enhanced chemical vapor deposition system and measuring the thermal properties using a custom-built modulated photothermal reflectance system. A novel approach of nanoseeding will be employed to reduce roughness and interface thermal resistance. Advanced materials characterization techniques will be used to identify defects in the films and relate to mean free path for phonon scattering for identifying the dominant defect controlling thermal transport in layered diamond thin films. The proposed research is significant and transformative because the results will be, to the best of our knowledge, the first comprehensive study on the effect of processing on the nanostructure, defects, and thermal transport mechanisms in NCD and layered NCD/MCD films with improved thermal properties.The proposed research has potentials for enormous payoffs because thermal management plays a critical role in several high-technology areas including optoelectronics, microelectronics, power electronics and microelectromechanical systems. In addition, with the current emphasis on conserving our limited natural resources for energy production, efficient thermal management strategies will result in direct savings in cooling costs leading to lower energy consumption and a significant positive environmental impact. An essential component of this research will be training and education of students and post docs, and dissemination of the results through publications in journals and presentations at conferences. The minority/women and high school students will be mentored and exposed to research through several programs at our university. A significant outreach to high schools is proposed through camps for teachers and students.