Nanomaterial enabled laser transfer for organic light emitting material direct writing

Abstract

Organic light emitting material direct writing is demonstrated based on nanomaterial enabled laser transfer. Through utilization of proper nanoparticle size and type and the laser wavelength choice, a single laser pulse could transfer well-defined and arbitrarily shaped tris-(8-hydroxyquinoline)Al patterns ranging from several microns to millimeter size. The unique properties of nanomaterials allow laser induced forward transfer at low laser energy (0.05 J/cm2) while maintaining good fluorescence. The technique may be well suited for the mass production of temperature sensitive organic light emitting devices.

Red-green-blue polymer light-emitting diode pixels printed by optimized laser-induced forward transfer

“…The OLED pixels fabricated by LIFT reach efficiencies on the range of conventionally fabricated devices and even surpass them in the case of blue pixels. Laser-induced forward transfer (LIFT), also known as laser direct-write, 1 is a class of printing techniques that have already been used to fabricate basic small-molecule organic light-emitting diodes (OLEDs) 2,3 and polymeric OLEDs (PLEDs). 4,5 OLEDs are a form of solid-state lighting, under intense research for commercial applications, 6,7 with OLED electronic displays of particular interest.…”

Dynamic spatial pulse shaping via a digital micromirror device for patterned laser-induced forward transfer of solid polymer films

“…In general, the use of a DRL [6] leads to a more confined absorption of the incident pulse energy and hence can result in a lower fluence required for flyer propulsion, as well as less damage to the donor and resultant flyer. DRLs of metals [6,7], polymers [8,9], or more complex materials [5] have been successfully demonstrated. Due to the high speed of the flyer (shadowgraph measurements have shown speeds varying from 34 ms −1 [10] to ~2 kms −1 [11], where flyer velocities with and without DRLs have been recorded at similar values [12]) and subsequent rapid deceleration when it collides with the receiver substrate, the flyer can experience significant forces that can result in damage.…”

“…As donor and receiver substrates are prepared independently, LIFT enables the deposition of materials on substrates that may be difficult via other fabrication methods. Multilayer donor materials have allowed the production of complex structures via LIFT, including metamaterials [2,3] and lightemitting diodes [4,5]. In general, the use of a DRL [6] leads to a more confined absorption of the incident pulse energy and hence can result in a lower fluence required for flyer propulsion, as well as less damage to the donor and resultant flyer.…”

“…Pulsed lasers, usually ranging from nanosecond to femtosecond pulse lengths, can be used for LIFT, with typical energy densities of a few tens to hundreds of mJ/cm 2 . Until recently, the majority of LIFT research has used focused or imaged laser pulses that had a Gaussian or 'top-hat' spatial intensity profile, with circular or rectangular beamshaping (with extension to "smart beam shaping" [16], or the use of custom masks [5]). Whilst individual deposits can be overlapped [17], this approach cannot be easily extended to produce less simple 2D structures.…”

Characterization of regular periodic surface structure by multi-pulse laser irradiation of a Zinc target

“…It carries certain advantages such as, no mask needed, high efficiency, selectivity, and localizability. In previous studies, a lot of work has been focused on the central holes formed on the substrate, which have a variety of applications, such as grapheme fabrication on the nickel [1] and organic light emitting diode (OLED) based on laser transfer [3] . However, the mechanisms of regular and deformed patterns at the outside region of the molten area have not been thoroughly understood, partly because the inevitable vaporizing and recasting of material results in complicated patterns around the molten area, even with femtosecond laser ablation [3−7] .…”