SBIR Phase I: MEMS Manufacturing Platform for Novel Emissive Displays

这个小型企业创新研究(SBIR)第一阶段项目将开发一种创新工艺，将数百万微米尺寸的硅芯片(微芯片)制造、组装和焊接成高产量和成品率的显示器背板。微米级器件的焊接技术与块状芯片压铸的焊接技术有根本的不同，因为表面张力增加，器件热负荷降低，为创新和创造价值提供了机会。该项目利用制造平台来制造和组装微米尺寸的LED(微LED)，每个微LED都有一个集成的“焊料凸块”，在转移时自动将微LED粘合到底板上。为了将这种方法扩展到多端子器件，如硅集成电路，我们将演示在单个微芯片内形成多个焊点连接的可行性。我们将根据详细的微芯片热模型筛选合金成分和工艺参数，并开发用于对所选合金进行图案化的MEMS工艺。我们将研究在我们的组装条件下焊料的润湿特性，以控制扩散。我们将利用这些结果在第一阶段演示一个简单的微芯片电路，并在第二阶段使用这里开发的技术和设计规则来构建像素级驱动器(平板显示器中取代TFT背板所需的基本元素)。该项目的更广泛影响/商业潜力源于开发一种创新的microLED显示产品，该产品比最先进的LCD消耗更少的能源，延长了便携式应用的电池寿命，并可能在固定应用中每年节省0.86quad的美国能源。这些产品中的TFT背板是主要的成本驱动因素(尤其是对于更大的显示器)。第一阶段的成功将证明消除TFT背板的方法的可行性，并以降低制造成本、降低最低制造规模和资本设备成本的形式带来显著的长期好处。更低的制造成本将推动快速的市场渗透，增加这项技术的经济和环境影响。较低的资本成本和制造规模将使国内制造变得经济。美国显示器制造业的增长将导致制造业就业机会和国民生产总值的增加，并通过向国防部提供国内显示器产品来增强国家安全。将多终端设备集成到这个制造平台中的能力，也将使这种创新的制造设备在未来扩展到新的行业。

This Small Business Innovation Research (SBIR) Phase I project will develop an innovative process for fabricating, assembling and soldering millions of micron-sized silicon chips (microChips) into a display backplane with high-throughput and yield. Solder technologies for micron-sized devices are fundamentally different than those for bulk chip die-casting, due to increased surface tension and decreased device-thermal-load, providing an opportunity for innovation and value creation. This project leverages a manufacturing platform for fabricating and assembling micron-sized LEDs (microLEDs), each with a single integrated "solder bump" that automatically bonds the microLED into the backplane upon transfer. To extend this approach to multi-terminal devices such as silicon integrated circuits, we will demonstrate feasibility of forming multiple solder connections within a single microChip. We will screen alloy compositions and process parameters against detailed microChip thermal models, and develop a MEMS process for patterning the selected alloys. We will study the wetting characteristics of the solder under our assembly conditions to control spreading. We will use these results to demonstrate a simple microChip circuit in Phase 1, and use the technologies and design-rules developed here to build a pixel-level driver in Phase 2 (the fundamental element needed to replace the TFT backplane in flat-panel displays).The broader impact/commercial potential of this project stems from development of an innovative microLED display product that consumes less energy than state-of-the-art LCDs, extending battery life in portable applications, and potentially saving 0.86 Quads of U.S. energy per year in stationary applications. The TFT backplane in these products is the primary cost-driver (particularly for larger displays). Success in Phase 1 will prove the feasibility of an approach to eliminate the TFT backplane, with significant long-term benefits in the form of reduced manufacturing costs and reduced minimum manufacturing scale and capital equipment costs. Lower manufacturing cost will drive rapid market penetration, increasing the economic and environmental impacts of this technology. Lower capital costs and manufacturing scale will enable economic domestic manufacturing. The growth of a U.S. display manufacturing industry would lead to increased manufacturing jobs and gross national product, as well as enhanced national security through a domestic supply of display products to the Defense Department. The ability to integrate multi-terminal devices into this manufacturing platform will also allow this innovative manufacturing equipment to expand into new industries in the future.