Research staff develops direct laser writing system for high-resolution, high-efficiency nanofabrication

Peripheral photoinhibition (PPI) direct laser writing (DLW) is a lithography method used to manufacture intricate 3D nanostructures which are broadly employed in photonics and electronics. PPI-DLW makes use of two beams, one to excite the substrate and trigger polymerization and the opposite to inhibit and quench the excitation on the edges. The capability is proscribed in some techniques, which may be improved by means of multifocal arrays. However, computing these beams is each time- and memory-intensive.

Recently, a bunch of researchers from Zhejiang University developed a parallel peripheral-photoinhibition lithography (P³L) system that may obtain greater effectivity nanoscale fabrication. Their work is revealed in Advanced Photonics

“The P³L system uses two channels, which allows the execution of different printing tasks and permits the system to fabricate highly complex structures with different periodicities,” says senior writer Xu Liu.

The P³L system consists of a bodily association of eight modules. The system begins with two printing channels, consisting of an excitation stable spot and a doughnut-shaped inhibition beam. The two beams are first stabilized and are then break up into two sub-beams utilizing a polarization filter. This permits the person on-off management of every sub-beam by means of an acoustic-optical modulator. Next, the 2 sub-beams are recombined to regain the excitation and inhibition beams. The beams are then modulated utilizing spatial mild modulators. Finally, the 2 beams are mixed and handed by means of a microscope, after which they deal with the substrate as two spots.

The particular person management of every sub-beam permits the printing of nonperiodic and complex patterns concurrently, with out compromising on scanning pace, thereby doubling the effectivity of the system. Adjusting the place and separation of the 2 spots is simple. These options make the proposed system extra versatile and purposeful than typical techniques with uniform focus management.

The researchers confirmed the feasibility and potential of the system by fabricating a wide range of nanostructures. They first fabricated a 2D sub-40 nm nanowire. A sub-20 nm-thick suspended nanowire was fabricated as properly. After that, the researchers created two rows of alphabet patterns by printing dots, 200 nm aside. Finally, they fabricated 3D buildings, together with nonperiodic cubic frames, hexagonal grids, wire buildings, and spherical architectures, all demonstrating distinctive decision.

The an identical on-off management of every focus will increase the pliability of the system and permits the speedy fabrication of advanced, nonperiodic patterns and buildings. The parallel scanning function of the system additionally reduces the time price required to manufacture large-scale, advanced buildings and patterns. Moreover, the brand new P³L system achieves a lithography effectivity that’s twice that of typical techniques, no matter whether or not the construction is uniform or advanced.

Discussing the longer term potential of the work, Xu Liu says, “Multifocus parallel scanning and PPI have the ability to overcome the current challenges in DLW optical fabrication and enhance the fabrication of blazed gratings, microlens arrays, microfluidic structures, and metasurfaces. The proposed system could, furthermore, facilitate the realization of portable, high-resolution, high-throughput DLW.”

Based on these outcomes, it’s clear that the proposed P³L system will function a useful gizmo for the event of a variety of fields that use nanotechnology.