This article compares the thermomechanical behavior of 3-D inkjet-printed microelectronics devices relative to those fabricated from traditional methods. It discusses the benefits and challenges in the adoption of additive manufacturing methods for microelectronics manufacture relative to conventional approaches. The critical issues related to the design and reliability of additively manufactured parts and systems stem from the change in the manufacturing process and the change in materials utilized. This study uses numerical modeling techniques to gain insight into these issues. This article is an extension of the same topic presented at the 2018 IEEE Electronics Packaging Technology Conference. An introduction providing an overview of the area, covering salient academic research activities and discussing progress toward commercialization is presented. The state-of-the-art modular microelectronics fabrication system developed within the EU NextFactory project is introduced. This system has been used to manufacture several test samples, which were assessed both experimentally and numerically. A full series of JEDEC tests showed that the samples were reliable, successfully passing all tests. The numerical model assessing the mechanical behavior of an inkjet-printed structure during layer-by-layer fabrication is presented. This analysis predicts that the stresses induced by the UV cure process are concentrated toward the extremities of the part and, in particular, in the lower layers which are constrained by the print platform. Subsequently, a model of a multilayer microelectronics structure undergoing JEDEC thermal cycling is presented. The model assesses the differences in mechanical properties between a conventional FR4/copper structure and an inkjet-printed acrylic/silver structure. The model identified that the influence of the sintering process on subsequent material properties, behavior of the inject-printed structure, and reliability of the inject-printed structure is significant. Key findings are that while stresses in the conventional and inkjet boards are relatively similar, the inkjet-printed board exhibits significantly greater deformation than the standard board. Furthermore, the mechanical stresses in the inkjet fabricated board are strongly dependent on the elastic modulus of the sintered silver material, which, in turn, is dependent on the sintering process.

中文翻译：

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喷墨印刷电子包装的相对可靠性

本文比较了3D喷墨打印微电子设备与传统方法制造的设备的热机械性能。它讨论了相对于传统方法，采用增材制造方法进行微电子制造的好处和挑战。与增材制造零件和系统的设计和可靠性有关的关键问题源于制造工艺的变化和所用材料的变化。这项研究使用数值建模技术来深入了解这些问题。本文是在2018 IEEE电子封装技术大会上提出的同一主题的扩展。简介概述了该领域，介绍了重要的学术研究活动并讨论了商业化的进展。介绍了EU NextFactory项目中开发的最先进的模块化微电子制造系统。该系统已用于制造多个测试样品，并通过实验和数值评估。JEDEC的完整系列测试表明，样品是可靠的，并成功通过了所有测试。提出了评估逐层制造过程中喷墨打印结构的机械性能的数值模型。该分析预测，由UV固化过程引起的应力集中在零件的末端，特别是在受打印平台约束的下层。随后，提出了进行JEDEC热循环的多层微电子结构模型。该模型评估了常规FR4 /铜结构和喷墨打印的丙烯酸/银结构之间的机械性能差异。该模型表明，烧结工艺对随后的材料性能，注射打印结构的行为以及注射打印结构的可靠性的影响是显着的。关键发现是，尽管常规板和喷墨板的应力相对相似，但喷墨印刷板的变形要比标准板大得多。此外，喷墨制造的板中的机械应力在很大程度上取决于烧结的银材料的弹性模量，而该弹性模量又取决于烧结过程。