Manufacturing Functional Polymer Surfaces by Direct Laser Interference Patterning (DLIP): A Polymer Science View

BARBERO, CESAR ALFREDO; ACEVEDO, DIEGO FERNANDO

Nanomanufacturing

mdpi

Año: 2022 vol. 2 p. 229 - 264

Direct laser interference patterning (DLIP) involves the formation of patterns of lightintensity using coherent laser light beams that interfere between them. Light on the ultraviolet(<350 nm) and NIR (800–2000 nm) is absorbed in chromophores present in the polymer structure orin loaded absorbing species (dyes, polymers, nanoparticles). The absorbed light induces photother-mal/photochemical processes, which alter permanently the topography of the polymer surface. Thesuccess of DLIP at different wavelengths is discussed in relation to the optical/thermal propertiesof the polymers and previous data on laser ablation of polymers. The size of the pattern is relateddirectly to the wavelength of the light and inversely to the sine of the angle between beams andthe refractive index of the external medium. In that way, nanometric structures (<100 nm) could beproduced. Since the patterning occurs in a single short pulse (<10 ns), large surfaces can be modified.Both bacterial biofilm inhibition and human cell differentiation/orientation have been achieved.Large improvements in technological devices (e.g., thin film solar cells) using DLIP structured sur-faces have also been demonstrated. Prospective application of DLIP to common polymers (e.g.,Teflon®) and complex polymeric systems (e.g., layer-by-layer multilayers) is discussed on the basis ofreported polymer data.