Session: 16-01-01: Government Agency Student Poster Competition

Paper Number: 150084

150084 - Multi-Layered Additive Manufacturing for Device Fabrication 

The additive manufacturing of multilayered materials from multi-component inks would be revolutionary for the fabrication of electronic devices, optical and protective coatings, and biological substrates, by reducing production costs and expanding the flexibility of design. This is a completely novel technology, which is based on the stratification of different solvents and particles/polymers into shell formations due to their differing vapor pressures and the solvent-particle/polymer interactions. Droplet printing is a high throughput printing method, but currently requires multiple printheads for each layer formed, which is expensive and time consuming. Unlike other 3D printing methods, inkjet printing does not require vacuum or contact with the substrate. Additionally, inkjet printing is relatively inexpensive and has fewer limitations when compared to other thin film fabrication methods like lithography, epitaxial growth, chemical vapor deposition, and sputtering, which require labor intensive and cost-prohibitive processing. The field of multi-component inks for multilayer printing is currently largely unexplored. Some work has been done to create segregated-layer thin films, but these dynamics are either dependent on sedimentation or exploiting a size difference between  particle types. Sedimentation-based stratification necessitates an unstable dispersion, making it a bad candidate for 3D printing. Solvent-based stratification, on the other hand, allows for the creation of stable and tunable inks which can be easily printed and adapted to a variety of applications. We hypothesize that if we create a multi-solvent system where the components have different vapor-liquid equilibria, our droplet will form a shell structure, and appropriately functionalized particles and polymers will preferentially separate into different solvent layers. To demonstrate this novel printing technique, a capacitor test system will be made using thiolated-silver and polystyrene nanoparticles on a gold-coated wafer, agnostic of gravitational based segmentation and relative particle size. To accomplish this, solvents and particle coatings are chosen to maximixe layer separation, while maintaining a stable dispersion. The solvent ratios and dispersion concentrations are optimized using cameras and confocal microscopy to monitor layer formation. Using the data collected on contact angles and solvent stratification, the test system is used to analyze layer morphology with optical microscopy, scanning electron microscopy (SEM), and UV-visible absorption spectroscopy (UV-Vis). The particles can then be sintered and the devices can be tested for capacitance. Once consistent and repeatable droplets have been established, the inks and printing procedures will be optimized for 3D printing into larger films with consistent architecture. Additionally, this technique can be expanded past three layer devices and applied to other thin layer materials in a variety of fields.

Presenting Author: Chloe Kekedjian Boston University

Presenting Author Biography: Chloe is a third year PhD candidate at Boston University in Materials Science and Engineering. She graduated from Georgetown University with a bachelors degree in chemistry in 2022. Her research background is in the optical and magnetic properties of nanomaterials. As a graduate student, her research utilizes properties of self-assembly and inkjet printing to create multilayered films and devices.

Authors:

Chloe Kekedjian Boston University
John William Boley Boston University