Aerosol Jet Deposition of Samarium-doped Ceria Films.

摘要

Direct write processes include a range of additive manufacturing technologies. These technologies are employed to fabricate structures by depositing layer upon layer of functional material. The feature resolutions obtained are often in the micron or sub-micron range. This thesis focuses on use of the Aerosol Jet direct write printing process, which shows promise for the fabrication of ceramic films due to its fine feature resolution and flexibility with printing complex features. This study identifies significant process parameters and their relationship to the process output for deposition of Samarium-doped Ceria (SDC) nano-ink. A design of experiments approach is used to generate a model where height and width of the printed tracks are the response variables of interest. Initial feasible operating ranges for each process parameter were identified. Then fractional factorial screening experiments were designed to identify the significant factors affecting the response variables in the study. Two distinct regression equations were generated to predict width and height. Validation experiments were run to confirm the actual values as compared with the predicted ones. For height, the experiment results suggested lack of curvature as well as the standard error and R-squared values were found satisfactory. For width, a higher order model was designed referring to the results of the validation experiment. For the higher order model a three factor three level experiment was considered. The higher order model gives a much lesser standard error and better fit of residuals as compared to the screening model for width. In addition, the study includes a brief discussion on use of Aerosol Jet printing system to manufacture high aspect ratio structures in addition to its application in thin film deposition. The work further demonstrates printing of a high aspect ratio micro-pillar array as a proof of this concept.