Bottom-Up Synthesis of Nickel and Copper Nanoparticle Ink for Aerosol Jet Printing

The production of microelectronics is currently dominated by subtractive manufacturing methods, which have proven to be successful, but are expensive, time-consuming, and generate needless waste. In contrast, additive manufacturing methods are much cheaper, more efficient, and produce little to no waste. Additive manufacturing utilizes metal nanoparticle ink for the printing of microelectronic devices. This process is known as direct writing. Since this technology is in its infancy, only a few metal nanoparticle inks are commercially available. In response to this deficiency, nickel and copper nanoparticle inks were developed and printed using an Optomec-200 Aerosol Jet Printer. The nanoparticles were synthesized from metal salts (Nickel(II) acetate and Copper(II) sulfate) using the Polyol method. The particles were capped with Polyvinylpyrrolidone (PVP) and reduced using Sodium borohydride (NaBH4) while suspended in Ethylene Glycol. The particles were then analyzed using XRD, DLS, and TEM. Surface Acoustic Wave (SAW) devices were printed on a piezoelectric substrate to show the viability of the nanoparticle ink. The devices are to be characterized, optimized, and utilized in the pursuit of high temperature sensors that can withstand neutron bombardment. These sensors are intended to be used in the hot cell of a nuclear reactor