Prism-Based Laser Interference Lithography System for Simple Multibeam Interference Lithography

Abstract

Laser interference lithography is a powerful technique of subwavelength-scale patterning. However, this technique requires a complicated optical system, the precise control and complexity of which increases exponentially with increasing number of beams. In this study, a compact prism-based laser interference lithography system using optical fibers and a prism was proposed to simplify the technique. In this system, the beam splitter and mirrors in a typical laser interference lithography system were replaced by a designed prism, and the pattern could be easily changed by only changing the prism, without other modification, irrespective of the number of beams required. In addition, because the laser and the laser interference lithography system are connected by an optical fiber, the system can be moved easily and flexibly. The fabrication of various submicroscale line patterns, holes, and dot patterns with a 270–1400 nm pitch was achieved using the proposed laser interference lithography system.

Direct Laser Interference Ink Printing Using Copper Metal–Organic Decomposition Ink for Nanofabrication

“…The results of the simulations match those calculated using Equation ( 2), and Λ was found to be close to the theoretical values, with 1396.3 and 1167.2 nm for the UV-fused silica and N-BK7 prisms, respectively. Although our setup in this study included a different convex lens from that used in our previous study [44], the change in the pitch of the interference pattern owing to the convex lens was negligible, and Equation ( 2) Figure 6a shows two strong peaks corresponding to Cu 2p 1/2 and 2p 3/2 and two weak Cu 2+ peaks. The XPS data show that the sample fabricated at a scan speed of 17 mm/s contains fewer copper oxides than that fabricated at 5 mm/s, as a large number of copper oxide peaks are observed in the XPS profile of the latter (Figure 6b).…”

“…The results of the simulations match those calculated using Equation (2), and Λ was found to be close to the theoretical values, with 1396.3 and 1167.2 nm for the UV-fused silica and N-BK7 prisms, respectively. Although our setup in this study included a different convex lens from that used in our previous study [44], the change in the pitch of the interference pattern owing to the convex lens was negligible, and Equation ( 2) remained valid even though the beam was not collimated. Figure 6a shows two strong peaks corresponding to Cu 2p1/2 and 2p3/2 and two weak Cu 2+ peaks.…”

“…These beams produce laser interference, and the beam intensity attains a periodic sinusoidal profile. Subsequently, as mentioned in our previous study [44], the pitch of the pattern can be calculated using Equation (2):…”

“…When the beams cross each other, the power distribution changes to a periodic pattern, and the period of these patterns can be smaller than the wavelength of the laser. This phenomenon has been used in laser interference lithography (LIL) [37][38][39][40][41][42][43][44] and direct laser interference patterning (DLIP) [45][46][47][48][49]. Although the present method, DLIIP, is similar to DLIP, DLIP uses laser interference for ablation, i.e., it is a subtractive process and, therefore, requires a high power.…”

Fabrication System for Large-Area Seamless Nanopatterned Cylinder Mold Using the Spiral Laser Interference Exposure Method

“…In recent years, nanotechnology has developed rapidly with a focus on developing cost-effective methods for the fabrication of nanoscale patterns for large areas [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Nanoimprint lithography (NIL) is a low-cost and largearea processing method for fabricating nanopatterns.…”