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The use of laser induced forward transfer (LIFT) techniques for printing materials for sensor and electronics applications is growing as additive manufacturing expands into the fabrication of functional structures. LIFT is capable of achieving high speed/throughput, high-resolution patterns of a wide range of materials over many types of substrates for applications in flexible-hybrid electronics. In many LIFT applications, the use of a sacrificial or laser-absorbing donor layer is required despite the fact that it can only be used once. This is because the various types of release layers commonly in use with LIFT are completely vaporized when illuminated with a laser pulse. A better solution would be to employ a reusable laser absorbing layer to which the transferable ink or material is attached and then released by a laser pulse without damage to the absorbing layer, therefore allowing its repeated use in subsequent transfers. In this work, we describe the use of two types of reusable laser-absorbing layers for LIFT. One is based on an elastomeric donor layer made from poly(dimethylsiloxane) or PDMS, while the other is based on a ceramic thin film comprised of indium tin oxide (ITO). These release layers have been used at NRL to transfer a wide range of materials including fluids, nanoinks, nanowires and metal foils of varying size and thickness. We will present examples of both PDMS and ITO as donor layers for LIFT and their reusability for laser printing of distinct materials ranging from fluids to solids.
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This content will become publicly available on July 8, 2026
A CFD Study of the Influence of Porous Structure Placement on Jet Formation in Laser-Induced-Forward-Transfer (LIFT) Printing
Abstract Laser-Induced Forward Transfer (LIFT) printing is a highresolution, non-contact, laser-based direct-writing technology suitable for various materials. The LIFT process is limited by its one-to-one correspondence between laser pulses and jet formation, which restricts the printing throughput and complicates scaling for high-speed operations. To address this challenge, we propose a novel strategy to integrate a porous structure below the donor slide in the LIFT system. The porous structure is expected to facilitate the formation of multiple jets from a single laser pulse, thereby overcoming traditional throughput limitations. In this study, we developed a computational fluid dynamics (CFD) model to verify the proposed idea. The findings confirmed that the formation of multiple jets induced by a single laser pulse can be achieved by manipulating the dynamics of bubble expansion within the porous structures. The simulations also demonstrated that variations in the size, spacing, and positioning of the porous structures, along with the initial bubble pressure, can significantly influence jet characteristics. This enables precise control over jet width and length, suggesting a viable approach to achieving high-throughput, high-efficiency LIFT printing through the deployment of porous structures.
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- Award ID(s):
- 2441995
- PAR ID:
- 10650612
- Publisher / Repository:
- American Society of Mechanical Engineers
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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