Low-cost inkjet printing of thin-film mullite structures

A commodity inkjet printer was modified to print layered ceramic structures on<br> stiff glass substrates, using inks in the form of sols with mullite stoichiometry.<br> The sol composition was optimized in terms of ink viscosity, surface tension,<br> and evaporation properties. The ink was then fed into a multi-nozzle commodity<br> printer head and deposited by ink-jetting. Thin lines without bulges with a thickness<br> of ∼1.8 μm with concave profile and a line width of ∼100 μm were successfully<br> printed on fused silica substrates. The presence of mullite was confirmed<br> by Raman spectroscopy and XRD after sintering of printed structures.