Investigations into Droplet-Based Microelectrofluidic Technology for Hot Spot Cooling and Thermal Management in Integrated Circuits

特征尺寸的减小和封装密度的增加使得热问题在集成电路（IC）设计中变得极其重要。IC中不均匀的热图和热点会导致物理应力和性能下降，并且还会降低可靠性。本研究计画主要针对嵌入式散热方法与IC热管理设计流程，其目的是开发基于微流体技术的芯片散热新技术，并将此技术应用于IC设计流程。它利用了杜克大学最近DARPA资助的一项研究成果，该研究成果导致了一种新颖的基于电润湿的液滴传输技术。它是基于电压控制下离散微升和纳升大小的液滴的高速电润湿传输。冷却液可以在时钟电压控制下通过2D电极阵列以用户定义的模式输送，而无需外部泵和阀门。此外，液体流量本身会随着温度的升高而增加。因此，芯片上的局部热区域将增加局部应用的冷却，而无需外部传感器。该项目还专注于流体路径的架构设计，该架构将传输液滴进行对流冷却。虽然在设计期间静态地分配液滴路径，但是在运行期间动态地确定液滴传输的速率。正在开发模拟和分析工具，以确定在现场操作期间不同通道和不同时间的液滴传输速率。正在研究的其他主题包括液滴路由协议和液滴布局优化技术。该项目将导致一个独立的，自我调节的，低功耗（微瓦）芯片冷却技术。从这项工作中获得的见解预计将为新一代用于计算和通信的嵌入式系统以及高端高速计算平台铺平道路。电源管理和散热问题被广泛视为IC发展的主要障碍;该项目有望帮助克服这些障碍。该项目也是两个不同研究社区之间的重要桥梁。它为微流体领域的研究人员提供了一个主要的应用驱动程序，用于继续研究纳升和皮升尺度的液滴流方法。另一方面，它使IC设计人员能够利用液滴流技术的进步进行芯片冷却。

Decreasing feature sizes and increasing package densities are making thermal issues extremely important in integrated circuit (IC) design. Uneven thermal maps and hot spots in ICs cause physical stress and performance degradation, and they also reduce reliability. This research project is focused on embedded cooling methods and an IC design flow forthermal management.The goal of the project is to develop new techniques for chip cooling based on droplet microfluidics, and to relate this technology to the integrated circuit (IC) design flow. It leverages a recent DARPA-funded research effort at Duke University that led to a novelelectrowetting-based droplet transport technology. It is based on high-speed electrowetting transport of discrete microliter- and nanoliter-sized droplets under voltage control. Cooling liquids can be transported, in user-defined patterns, under clocked-voltage control over a 2D-array of electrodes without the need for external pumps and valves.In addition, liquid flow is inherently increased with increasing temperature. Thus, local hot areas on a chip will have increased cooling applied locally without the need for external sensors.The project is also focused on the design of the architecture for fluidic pathways, which will transport droplets for convective cooling. While the droplet paths are statically allocated during design time, the rate of droplet transport is dynamically determined during run-time. Simulation and profiling tools are being developed to determine the rate of droplet transport on different channels and at different times during field operation. Additional topics being investigated include protocols for droplet routing and optimization techniques for droplet layout. This project will result in a self-contained, self-regulated, and low power ( a microwatt) chip cooling technique. The insights gained from this work are expected to pave the way for a new generation of embedded systems for computing and communications, as well as high-end, high-speed computation platforms. Power management and thermal problems are being widely seen as major roadblocks in the evolution of ICs; this project is expected to help overcome these roadblocks. This project also serves as an important bridge between two diverse research communities. It provides researchers from the microfluidics area with a major application driver for continued research into droplet-flow methods at the nanoliter and picoliter scales. On the other hand, it enables IC designers to leverage advances in droplet-flow technology for chip cooling.