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The potential to deposit minute amounts of material from a donor to an acceptor substrate at precise locations makes laser-induced forward transfer (LIFT) a frequently used tool within different research fields, such as materials science and biotechnology. While many different types of LIFT exist, each specialized LIFT application is based on a different underlying transfer mechanism, which affects the to-be-transferred materials in different ways. Thus, a characterization of these mechanisms is necessary to understand their limitations. The most common investigative methods are high-speed imaging and numerical modeling. However, neither of these can, to date, quantify the material deposition. Here, analytical solutions are derived for the contact-based material deposition by LIFT, which are based on a previously observed equilibrium state. Moreover, an analytical solution for the previously unrecognized ejection-based material deposition is proposed, which is detectable by introducing a distance between the donor and acceptor substrates. This secondary mechanism is particularly relevant in large scale production, since each deposition from a donor substrate potentially induces a local distance between the donor and acceptor substrates.

We have observed the concentric deposition patterns of small molecules transferred by means of laser-induced forward transfer (LIFT). The patterns comprised different parts whose presence changed with the experimental constraints in a mode-like fashion. In experiments, we studied this previously unknown phenomenon and derived model assumptions for its emergence. We identified aerosol micro-flow and geometric confinement as the mechanism behind the mass transfer and the cause of the concentric patterns. We validated our model using a simulation.