A Fundamental Study of a Surface Modification on Silicon Wafer Using Direct Laser Interference Patterning with 355-nm UV Laser

Abstract

The growing need for precision machining, which is difficult to achieve using conventional mechanical machining techniques, has fueled interest in laser patterning. Ultraviolet (UV) pulsed-lasers have been used in various applications, including the micro machining of polymers and metals. In this study, we investigated direct laser interference patterning of a silicon waver using a third-harmonic diode-pumped solid-state UV laser with a wavelength of 355 nm. Direct laser lithography is much more simple process compare to other submicro processing method. We have studied interference patterning for silicon wafers as a basic research for direct laser interference patterning on wafer surfaces without mask. And Finite element analysis (FEA) was performed for a 150° biprism using modeling software (COMSOL Multiphysics 5.4) to determine changes in the periodic patterns according to the focusing distance in the direct interference lithography experiment. In further study, we expect this technique to be applied to direct laser interference lithography on metals.

Few-ns, kW peak power Q-switched pulses from orange and red Pr:YLF lasers

“…9,10) Among these, we previously demonstrated the Co 2+ -doped spinel crystal (Co 2+ :MgAl 2 O 4 ) to be an outstanding SA for passively Q-switched visible Pr 3+ :LiYF 4 (Pr:YLF) lasers, [11][12][13] yielding a simple approach for pulsed visible and UV sources demanded for materials processing, 14) lithography, 15) and wafer inspection. 16) UV lasers enable non-thermal processing by direct chemical bond breaking in the processed materials. 17) Pulsed UV lasers are also needed in plasma spectroscopy.…”