Department of Materials Science and Engineering, Frederick Seitz Materials Research Laboratory, Micro and Nanotechnology Laboratory, University of Illinois, 1304 West Green Street, Urbana, IL 61801, USA.
Proc Natl Acad Sci U S A. 2011 Jun 21;108(25):10072-7. doi: 10.1073/pnas.1102650108. Epub 2011 Jun 10.
Properties that can now be achieved with advanced, blue indium gallium nitride light emitting diodes (LEDs) lead to their potential as replacements for existing infrastructure in general illumination, with important implications for efficient use of energy. Further advances in this technology will benefit from reexamination of the modes for incorporating this materials technology into lighting modules that manage light conversion, extraction, and distribution, in ways that minimize adverse thermal effects associated with operation, with packages that exploit the unique aspects of these light sources. We present here ideas in anisotropic etching, microscale device assembly/integration, and module configuration that address these challenges in unconventional ways. Various device demonstrations provide examples of the capabilities, including thin, flexible lighting "tapes" based on patterned phosphors and large collections of small light emitters on plastic substrates. Quantitative modeling and experimental evaluation of heat flow in such structures illustrates one particular, important aspect of their operation: small, distributed LEDs can be passively cooled simply by direct thermal transport through thin-film metallization used for electrical interconnect, providing an enhanced and scalable means to integrate these devices in modules for white light generation.
现在，先进的蓝铟镓氮发光二极管（LED）具备的各种特性，使得它们有望替代现有照明基础设施，这对提高能源利用效率具有重要意义。进一步推进这项技术的发展，需要重新审视将这种材料技术整合到照明模块中的方式，这些模块能够管理光的转换、提取和分布，以最小化与操作相关的不利热效应，同时利用这些光源的独特方面来设计封装。我们在此提出了各向异性刻蚀、微尺度器件组装/集成和模块配置方面的思路，以非传统的方式解决这些挑战。各种器件演示提供了相关能力的实例，包括基于图案化荧光粉的薄型、柔性照明“胶带”和在塑料基板上的大量小型发光器。对这些结构中热流的定量建模和实验评估说明了其操作的一个特别重要的方面：小型分布式 LED 可以通过用于电连接的薄膜金属化进行被动式冷却，这为在用于白光产生的模块中集成这些器件提供了一种增强且可扩展的手段。
