Novel Substrate Manufacturing for Stretchable Printed Electronics
Stretchable electronics are being used in various applications such as wearable electronics, stretchable artificial skin, wearable chip devices for health monitoring and smart textiles, due to their excellent mechanical conformability through stretching, flexing, twisting, and folding. While most current processes use commercially available substrates for printed applications, their ability to stretch is limited. This work is focused on in-house production of elastomeric substrates with enhanced/tailorable dielectric properties for stretchable electronics. The addition of a dielectric filler is a logical solution to enable tailored dielectric properties, however, there are challenges in maintaining desirable mechanical properties in a compound, such as a recovery after stretch and low set. This work shows the creation of a thin stretchable dielectric substrate with a ferroelectric filler, barium strontium titanate (BST), in a base elastomer, butyl rubber (IIR). This elastomer shows good barrier and electrical properties for a variety of applications. The effect of BST loading on properties, such as dielectric and mechanical strength was evaluated. A stretchable conductive ink was selected for printing design for dielectric property measurements. Thus, the material offers good potential for stretchable electronics applications.