A Group of Cyclic Siloxane and Silazane Polymer Films as Nanoscale Electrolytes for Microbattery Architectures

Nanoscale (10-50 nm) thin films of cyclic siloxane and silazane polymers were synthesized by initiated chemical vapor deposition (iCVD). We have previously demonstrated that the non-line-of-sight iCVD synthesis process can create uniform conformal coverage of these films over complex nonplanar surfaces. This work will introduce the protocols used to convert these dielectric polymer films into ionic conductors at room temperature. The excellent thickness and morphological stability of these films will be demonstrated along with experiments that determine the ion content in the films. Finally, computational calculations will be used to elucidate the chemical nature of the ion doping and transport processes. These nanoscale, conformal, ionically conducting polymer thin films are attractive as a novel class of nanoscale electrolytes for emerging miniaturized or microbattery architectures such as three-dimensional (3D) batteries which combine high energy (due to high surface area) and power density (due to short ionic transport lengths) within small areal footprints.