• Journal of the Semiconductor & Display Technology
• /
• v.22 no.4
• /
• pp.26-31
• /
• 2023

We investigated the impact of NF₃ / H₂O remote plasma dry cleaning conditions on the SiO₂ etching rate at different preparation states during the fabrication of ultra-large-scale integration (ULSI) devices. This included consideration of factors like Si crystal orientation prior to oxidation and three-dimensional structures. The dry cleaning process were carried out varying the parameters of pressure, NF₃ flow rate, and H₂O flow rate. We found that the pressure had an effective role in controlling anisotropic etching when a thin SiO₂ layer was situated between Si₃N₄ and Si layers in a multilayer trench structure. Based on these observations, we would like to provide further guidelines for implementing the dry cleaning process in the fabrication of semiconductor devices having 3D structures.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.185-186
• /
• 2007

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.11
• /
• pp.1637-1642
• /
• 2010

In this paper, we present the fabrication of a high-quality diffractive-lens mold having submicron patterns, which is suitable for an ultra-slim optical system. In order to fabricate high-quality diffractive lens with a variety of submicron patterns, the multi-alignment method was used; high-resolution electron-beam lithography and FAB plasma etching were carried out to obtain the patterns. The most important key technology in the multi-alignment method is to reduce alignment error, lithography error, and etching error. In this paper, these major fabrication errors were minimized, and a high-quality diffractive lens with a diameter of $267\;{\mu}m$ (NA = 0.25), minimum pattern width of 226 nm, and thickness of 819 nm was successfully fabricated.

• Proceedings of the Korean Magnestics Society Conference
• /
• 2010.06a
• /
• pp.70-71
• /
• 2010

In this study, We fabricated FePt-based perpendicular patterned media using a selective combination of E-beam lithography and either Ar plasma etching (deposition-first process) or FePt lift-off (deposition-last process). We employed the deposition-last process to avoid chemical and structural disordering by impinging Ar ions (deposition-first process). For a patterned medium with 100 nm patterns made by this process, the out-of-plane coercivity was measured to be 5 fold larger than its in-plane value. The deposition-last process may be a promising way to achieve ultra-high density patterned media.