Structural characterization of He ion microscope platinum deposition and sub-surface silicon damage

Abstract

In this paper we studied helium ion beam induced deposition (HIBID) of Pt on a silicon wafer using the recently commercialized helium ion microscope (HIM) at 25 kV and low beam currents. The motivation of this work was to understand the impact of light, inert helium ions on deposition rate and structure purity, with some implications on the usefulness of HIM nano-machining for circuit modification. Two Pt-rich deposits with sub-micron dimensions were grown with HIBID at different ion beam currents. The pillar and substrate structure were studied using bright and dark field TEM images. The authors analyzed metal purity profile of the HIBID deposit on height using energy dispersive x-ray spectroscopy. The maximum Pt content measured reached 41%, which is the highest measured metal content of a HIBID-grown structure. TEM studies of the sub-surface damage to the Si shows more damage below the deposit grown at a higher beam current. The differences in amorphization layer thickness between the two different beam currents are discussed. A comparison to Pt deposition by Ga FIB and electron beam induced deposition is provided, along with conclusions regarding the usage of HIBID technology for circuit modification.

Tungsten-based pillar deposition by helium ion microscope and beam-induced substrate damage

“…The swelling heights (i.e., Si blister heights) are summarized in Fig. 18 For comparison, the beam is focused on the Si surface without gas injection, as shown in Figs. EDX analysis is used to clarify the composition and formation mechanism of the blisters.…”

Focused helium and neon ion beam induced etching for advanced extreme ultraviolet lithography mask repair

“…In this case, the authors concluded that, on actinic images, there was no difference between the repaired area and the non-repaired one. 5 Livengood et al 31,[34][35][36][37][38][39] have performed a dose-dependent study of He-beam induced damage in crystalline Si and Cu. Results demonstrated that no damage was observed up to a dose of $1 Â 10 15 ions/cm 2 .…”

Sub-10 nm writing: focused electron beam-induced deposition in perspective

“…[61], still ''significant amorphization below the deposit occurs'' during deposition with He ? [57]. The implantation of ions also leads to bubble formation.…”

“…and He ? ions give deposition rates of 0.5, 0.27, or 0.85 lm 3 /nC [55][56][57] for MeCpPtMe 3 at 25 keV. For electrons, the deposition rate is 0.0007 lm 3 /nC for ClAu(CO) at 5 keV [31] or 0.01 for CpPtMe 3 at 10 keV [58].…”