Production engineering research for the manufacture of novel electronically functional yarns for multifunctional smart textiles

该提案涉及研究和开发新的制造方法，通过将半导体器件集成到纱线中，将电子功能添加到纺织品的核心。纺织品是人类接触到的最常见的材料之一，但目前，纺织品的功能仅限于其外观和物理特性。人们对具有附加电子功能的多功能纺织品的兴趣越来越大：这些纺织品将提供更广泛的功能，包括传感、数据处理和与用户的交互，因此可以应用于广泛的应用领域。电子纺织品（e -纺织品）不仅需要性能良好，而且需要坚固耐用，穿着舒适，易于使用，磨损，洗涤和维护。目前，通过将电子设备附加或打印到纺织品表面（第一代）或在纺织品制造阶段添加电子功能（第二代），电子设备已与纺织品集成在一起。第一代电子纺织品总是会干扰服装的纺织性能；甚至是印在纺织品上的薄膜装置或电路。当纺织品符合形状时，有些区域弯曲，有些区域发生剪切变形：这两个因素对悬垂性和舒适度都很重要。针织和机织纺织品在弯曲和剪切时能够符合某种形状，然而，薄聚合物薄膜可以弯曲，但由于它不能剪切，它会弯曲和皱褶，而不是符合某种形状。第二代纺织品可能保留了纺织品的感觉，但在其应用方面受到限制，例如电气通路的创建和基于电极的传感。因此，Dias教授（PI）率先开发了一种平台技术，将半导体封装的骰子嵌入纱线的核心，以便将电子产品集成到纺织结构的核心。生产过程开始于封装片在细铜线上的回流焊接。载体纱平行放置，以提供提高抗拉强度的铜线填充包装骰子。然后将包片和载体纱封装在聚合物微豆荚中，以防止水分进入。微型吊舱和铜互连最后被额外的纤维包围，这些纤维在针织纤维护套内紧密地结合在一起，形成电子纱线（E-yarn）。该项目的目的是创造以可靠的自动化方式生产电子纱线的基础知识，并演示自动化试验生产线（TRL4）。研究人员已经证明了使用双端封装骰子以半自动方式生产电子纱线的能力。该研究计划将把这一专业知识扩展到基于半导体设备的电子纱线的可靠创造，该设备具有两个以上的终端，大大扩展了可以创造的电子纱线类型的范围。为了实现这一雄心勃勃的目标，必须解决以下研究领域：焊接半导体芯片的热能管理；焊片的封装；优化了用筛子覆盖铜线的技术，以防止其迁移到电子纱的表面；电子纱试验方法的发展。该提案涉及一种可以解决一系列电子纺织品应用的平台制造技术。这项研究将确保该技术能够提供所需的功能，满足实际使用的要求，并为电子纱线技术的商业化提供平台。项目成果将提高英国的行业能力，引领电子纺织品行业，预计到2028年将增长到50亿美元的市场；因此，提出的研究是及时的。[1] www.idtechex.com/research/reports/e纺织品- 2018 - 2028 -技术-市场——以及球员- 000613. - asp

This proposal is concerned with the research and development of new manufacturing methods that add electronic functionality to the heart of textiles by incorporating semiconductor devices into yarns. Textiles are one of the most common materials with which humans come into contact, but, at present, their functionality is limited to their appearance and physical properties. There is considerable and growing interest in multifunctional textiles with added electronic functionality: These will offer a far greater range of functionality that can include sensing, data processing and interaction with the user and, as a result, can be applied in a vast range of applications. Electronic textiles (E-textiles) need to not only perform well but also be robust, comfortable to wear and be readily used, worn, washed, and maintained.Currently, electronics have been integrated with textiles by either attaching or printing the electronics onto the surface of a textile (first generation), or the electronic functionality is added at the textile manufacturing stage (second generation). The first generation E-textiles will always interfere with the textile properties of a garment; even thin film devices or circuits printed on textiles. As a textile conforms to a shape some regions bend and some go into shear deformation: Both factors are important for drape and conformability. Knitted and woven textiles are able to conform to a shape as they bend and shear however, a thin polymer film can bend but, as it cannot shear, it will buckle and crumple rather than conform to a shape. The second generation textiles may retain a textile feel but are limited in their applications, such as the creation of electrical pathways, and electrode-based sensing. Therefore, Professor Dias (the PI) pioneered the development of a platform technology for embedding semiconductor packaged dice within the core of yarns, in order to integrate electronics into the heart of textile structures. The production process starts with re-flow soldering of package dice onto fine copper wire. A carrier yarn is placed in parallel to provide improved tensile strength to the copper wire populated with packaged dice. The package dice and carrier yarn are then encapsulated within polymer micro-pods to provide protection from moisture ingress. The micro-pod and copper interconnects are finally surrounded with additional fibres held tightly together within a knitted fibre sheath to create an electronic yarn (E-yarn).The aim of this project is to create the underlying knowledge to produce E-yarns in an automated fashion reliably, and to demonstrate an automated pilot manufacturing line (TRL4). The ability to produce E-yarns in a semi-automated fashion using two-terminal packaged dice has already been demonstrated by the investigators. The programme of research will extend this expertise to the reliable creation of E-yarns based on semiconductor devices with more than two terminals, massively extending the scope for the types of E-yarn that can be created. To achieve this ambitious goal the following research areas must be addressed: thermal energy management for soldering semiconductor dice; encapsulation of soldered dice; optimisation of the techniques of covering copper wires populated with dice to prevent their migration to the surface of the E-yarn; development of testing methods for the E-yarns. This proposal concerns a platform manufacturing technology that can address a range of E-textiles applications. The research will ensure that the technology can deliver the required functionality, meet the requirements of practical use, and provide the platform for commercialising the E-yarn technology. Project results will increase industry capability in the UK to lead the E-textile sector, which is expected to grow to a $5 billion market by 2028; hence the proposed research is timely.[1] www.idtechex.com/research/reports/e-textiles-2018-2028-technologies-markets-and-players-000613.asp