Microfluidic Stretchable Radio-Frequency Devices

Recently, the shrinking of the personal computer market has given a clear signal that it is time to divert our focus from the strategy of miniaturization of transistors to a different strategy with emerging technologies. As a new form of electronics, stretchable electronics has significantly advanced in the past few years by micro/nanofabrication of thin films of traditional stiff and hard materials such as silicon, metals, and ceramics, and especially subsequent transfer process on an elastic substrate. However, such a thin structure often suffers from high resistance that leads to low performance when long structures are required. This is particularly true for antennas in radio-frequency (RF) electronics. By introducing microfluidics into RF electronics, we found out that it was an excellent way to make high-performance stretchable RF electronics. Apart from antennas, the microfluidic approach was also adopted and further developed to various devices with integrated wireless communication. This fusion of microfluidics with RF electronics brings not only a lot of opportunities for researchers as a radically new research field, but also potentially commercial benefits for industry. As a new emerging field, a huge effort, ranging from fundamental science to technology development, is required to realize it. This paper illustrates the fundamentals in processing and relevant applications, and highlights recent advances in microfluidic RF electronics. The authors would like to inspire the electronics community to further exploit the advantages of this approach and accelerate innovations in this field.