Three-Dimensional Laser Printing of Macro-Scale Glass Objects at a Micro-Scale Resolution

Abstract

Three-dimensional (3D) printing has allowed for the production of geometrically complex 3D objects with extreme flexibility, which is currently undergoing rapid expansion in terms of materials, functionalities, as well as areas of application. When attempting to print 3D microstructures in glass, femtosecond laser-induced chemical etching (FLICE)—which is a subtractive 3D printing technique—has proved itself a powerful approach. Here, we demonstrate the fabrication of macro-scale 3D glass objects of large heights up to ~3.8 cm with an identical lateral and longitudinal feature size of ~20 μm. The remarkable accomplishment is achieved by revealing an unexplored regime in the interaction of ultrafast laser pulses with fused silica, which results in depth-insensitive focusing of the laser pulses inside fused silica.

Freeform Microfluidic Networks Encapsulated in Laser‐Printed 3D Macroscale Glass Objects

“…[34,53] For instance, macroscale 3D glass objects of large heights up to ≈3.8 cm with an identical lateral and longitudinal feature size of ≈20 µm can be fabricated. Actually, we have found that the depth-insensitive focusing of picosecond pulses at a certain condition allows the laser structuring can maintain an unchanged feature size from the bottom to the top of the glass without the additional compensation of the aberration originated from the refractive index mismatch between air and fused silica.…”

“…To fabricate 3D uniform glass microchannels with centimeter-scale length, introduction of a string of extra-access ports along the microfluidic channels has been adopted for ensuring homogeneous fabrication of the channels during the chemical etching. [34,49] The proposed approach allows monolithic fabrication of 3D freeform encapsulated microchannels and 3D printable glass structures with arbitrary lengths and flexible configurations on a glass substrate, paving the way for advanced manufacturing of 3D largescale all-glass microfluidic systems. [46][47][48] Moreover, 3D laser subtractive glass printing enables rapid manufacturing of macroscale glass objects with desirable shapes and a high precision down to several tens of micrometers due to unique polarization-insensitive and depth-insensitive processing characteristics of picosecond laser irradiation.…”

“…[12][13][14] Currently, one of the most representative 3D microfabrication techniques of fused silica is ultrashort pulse laser microfabrication. [34][35][36] However, controllable formation of freeform hollow microchannel with arbitrary length encapsulated in 3D printed glass structures has not yet been demonstrated, which is highly desirable for high-infidelity manufacturing of artificial organs, on-chip construction of biomimetic microenvironments, [37][38][39][40][41] as well as enrichment of the functions of continuous-flow microreactors (e.g., seamless integration of customized functional module for temperature control and on-line spectrometer monitoring). [24][25][26] In addition, suspended hollow structures with 3D shapes and a high precision in fused silica can be fabricated by combining room-temperature casting and sacrificial template replication.…”

A Microfluidic Mixer of High Throughput Fabricated in Glass Using Femtosecond Laser Micromachining Combined with Glass Bonding

“…Both the translation stages were controlled using a high-performance motion controller (A3200, Aerotech Inc., Pittsburgh, PA, USA). In our fabrication, the repetition rate of the laser was set to 100 kHz, and the laser pulse duration was set as 4 ps [25,26]. The laser focal spot was scanned along the pre-designed paths layer by layer with a layer spacing of 10 µm to produce the microchannels on both glass substrates.…”

Editorial for the Special Issue of 10th Anniversary of Micromachines

“…A total of 52 papers, including 42 original research articles, 9 review articles, and 1 brief report, are published in this Special Issue. A total of 14 out of the 52 papers in the Special Issue are selected as feature papers [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ].…”