Precision Nanoscale Printing: Optimization through Focused Ion Beam Techniques

Abstract

Due to its benefits, such as direct milling and deposition, focused ion beam (FIB) is attracting a lot of attention in nanopatterning. Similar to traditional lithography techniques, dosage still governs the degree of pattern conformance in FIB. However, a number of other factors, like the ion beam current, pixel size, and number of pixels in the bitmap file, all affect dose. In this paper, we looked at how the aforementioned characteristics affected dosage per unit area and, consequently, pattern conformity. It was discovered that to create well-separated nanohole arrays, a dose of roughly 7.5-8.6 pC/m2 or a bitmap file corresponding to 4000-5000 pixels/m2 at a beam current of 30 pA is reasonable. Despite producing improved conformance, direct pattern creating on the FIB working field is impractical for large-scale patterning. Finally, employing a dosage of 8.6 pC/m2, a somewhat larger scale nanohole array with a diameter and spacing of 100 nm was obtained. This article provides some recommendations for silicon substrate nanopatterning for photonic applications.