Silicon dioxide mask by plasma enhanced atomic layer deposition in focused ion beam lithography

Abstract

In this work, focused ion beam (FIB) lithography was developed for plasma enhanced atomic layer deposited (PEALD) silicon dioxide SiO hard mask. The PEALD process greatly decreases the deposition temperature of the SiO hard mask. FIB Ga ion implantation on the deposited SiO layer increases the wet etch resistivity of the irradiated region. A programmed exposure in FIB followed by development in a wet etchant enables the precisely defined nanoscale patterning. The combination of FIB exposure parameters and the development time provides greater freedom for optimization. The developed process provides high pattern dimension accuracy over the tested range of 90-210 nm. Utilizing the SiO mask developed in this work, silicon nanopillars with 40 nm diameter were successfully fabricated with cryogenic deep reactive ion etching and the aspect ratio reached 16:1. The fabricated mask is suitable for sub-100 nm high aspect ratio silicon structure fabrication.

Investigation of the Effects of Pulse-Atomic Force Nanolithography Parameters on 2.5D Nanostructures’ Morphology

“…These nanofabrication approaches, generally known as Scanning Probe Lithography (SPL) [4,7], are based on the use of AFM probes to directly fabricate nanostructures on the sample surface through various mechanisms, opening up a wide range of possible applications [8]. Compared to more conventional top-down fabrication techniques, such as Nanomaterials 2022, 12, 4421 2 of 16 those based on Electron Beam Lithography (EBL) [9,10], Focused Ion Beam (FIB) [11][12][13][14][15], or Ultra-Violet lithography (UV Lithography) [16], TBN techniques are cheaper, more flexible, environment-friendly and maskless, and target more materials [4]. Moreover, the same cantilever used for fabrication could be employed to image the structures immediately afterward [17].…”

Process Optimization of Amorphous Carbon Hard Mask in Advanced 3D-NAND Flash Memory Applications

“…The thinner PRs will result in pattern bending or collapse-wiggling in the etch process [7][8][9]. In recent years, amorphous carbon hard masks (ACHM) have been used in semiconductor device fabrication, replacing the conventional SiO 2 or Si 3 N 4 HM due to its robust film properties such as high transparency, high etch selectivity, high durability for plasma Asher and easy elimination by oxygen (O 2 ) plasma [10][11][12]. ACHM is characterized by an intermediate H content to amorphous carbon with sp2-bonded clusters, interconnected by a random network of sp3-bonded atomic sites.…”

Direct etching at the nanoscale through nanoparticle-directed capillary condensation

“…In particular, not only is it essential for the microelectronic industry 1 but also for the development of metamaterials, 2,3 metasurfaces, 4 plasmonics 5 and nanophotonics, 6 just to name a few examples. Although some applications can benefit from random nanostructuring techniques, 7 sophisticated and expensive nanolithography technologies are typically required, such as extreme UV lithography, 8 electron beam lithography, 9 ion beam lithography, 10 nanoimprint lithography 11 or scanning probe lithography. 12,13 In addition to these, alternative lowcost self-assembly nanopatterning methods have been proposed such as block copolymers 14 and, most relevant to this work, colloidal lithography.…”