Nanowires-based high-density capacitors and thinfilm power sources in ultrathin 3D glass modules

Abstract

This paper explores silicon nanowire technology for ultrathin high-density capacitors, supercapacitors and batteries. Development of such thin power components on glass or silicon will allow integration with other passive components as well as actives such as decoupling capacitors close to locic Ics to form 3D integrated passive and active devices (3D IPACs) that could then be surface-assembled onto glass packages leading to ultrathin self-powered modules or subsystems. Thinfilm integration of power components and passives on ultrathin glass 3D IPD substrates also leads to highly-efficient power distribution for miniaturized and high-performance electronic systems. The first part of the paper presents an analytical model to highlight the benefits of nanowire electrode-based high-density capacitors in capacitance density and operating frequency. The second part of the paper describes nanowire synthesis and a novel fabrication process for nanowire-electrode capacitors, and their characterization. Results indicate that nanowires enable a major breakthrough in thinfilm capacitors with ultrahigh volumetric capacitance densities of about 100 μF /mm 3 , 10X higher than all current capacitor technologies including trench, MLCC and tantalum capacitors.