Printed Electronics Fabrication of Laminated Conductors for Loss Reduction in RF Circuits

印刷电子学(PE)不同于传统的减法(例如，蚀刻)制造方法，并且是通过添加沉积导电或介电(绝缘)材料来制造电路/器件的多种方法之一。其中包括传统的印刷方法，如柔版印刷，以及最近开发的喷雾印刷技术。PE方法制造成本较低，适用于灵活的衬底。它们还没有在高频无线通信(RF)中得到广泛使用。原因是：射频电路通常由印刷在介质衬底上的导电金属图案组成。减法制造方法适合于产生作为单个厚(相对而言)导电层的导电轨道。但无论导体有多厚，所谓的电磁集肤效应都会导致电流在导体的一层薄层中流动。因此，有效电阻(以及此后不需要的功率损失)比如果电流可以在更大的导电轨道横截面上传播时的可能值更大。事实上，这一点在1951年就已经显示出来，即人们应该使用由非常薄的导电层组成的叠层导体，而不是单一的导电层，这些导电层被非常薄的介质材料隔开，厚度恰好合适。因此，这种叠层导体的电磁场穿透可能会有许多皮深厚，因此电流将流经可用导体横截面的较大部分。这极大地降低了功率损耗。但减法制造方法不适用于制造叠层导体电路。这项研究将使用计算电磁学分析来设计叠层导体电路，并使用PE挠性印刷来制造它们，以努力开始使PE制造方法可用于射频电路。一种可能的应用是由一家加拿大公司开发的，这是世界上第一个针对安全和军事人员的完全集成的先进头部保护解决方案之一。

Printed electronics (PE) differs from conventional subtractive (eg. etching) fabrication methods and is insteadone of a number of methods to fabricate circuits/devices by additively depositing conducting or dielectric(insulating) material. These include traditional printing methods like flexography, and more recently developedtechniques like aerosol-jet printing. PE methods offer lower fabrication costs and are suited to flexiblesubstrates. They have not yet found widespread use at high wireless communications (RF) frequencies. Thereason is this : RF circuits are usually comprised of conducting metallic patterns printed on dielectricsubstrates. Subtractive fabrication methods are suited to produce conducting tracks as single thick (relativelyspeaking) conducting layers. But no matter how thick the conductor is, the so-called electromagnetic skin effectresults in the current flowing within a thin layer of the conductor. Thus the effective resistance (and henceunwanted power losses) is larger than it could be if the current could be made to spread over a larger crosssection of the conducting track. How this can be achieved was in fact shown in 1951, namely that instead of asingle conducting layer one should use laminated conductors comprised of very thin conducting layersseparated by extremely thin dielectric material, of just the correct thicknesses. Electromagnetic fieldpenetration of this laminated conductor can then be many skin depths thick and the currents will as a resultflow over larger portions of the available conductor cross-sections. This results in greatly decreased powerlosses. But subtractive fabrication methods are not suited to making laminated conductor circuits. This researchwill use computational electromagnetics analysis to design laminated conductor circuits, and PE flexography tofabricate them in an effort to start making PE fabrication methods available for RF circuits. One possibleapplication is by a Canadian company developing one of the world's first fully integrated advanced headprotection solutions for security and military personnel.