Helium ion beam induced growth of hammerhead AFM probes

The authors report the direct-write growth of hammerhead atomic force microscope (AFM) probes by He+ beam induced deposition of platinum-carbon. In order to grow a thin nanoneedle on top of a conventional AFM probe, the authors move a focused He+ beam during exposure to a PtC precursor gas. In the final growth stage, a perpendicular movement of...

Impact of pixel-dose optimization on pattern fidelity for helium ion beam lithography on EUV resist

This paper presents a heuristic model for scanning helium ion beam lithography (SHIBL) in a EUV chemically amplified resist. The model employs a point-spread function to account for all physical and chemical phenomena involved in the resist activation. Ion shot noise effects are accounted for using Poisson statistics. Our model shows a good...

High-resolution direct-write patterning using focused ion beams

Over the last few years, significant improvements in sources, columns, detectors, control software, and accessories have enabled a wealth of new focused ion beam applications. In addition, modeling has provided many insights into ion-sample interactions and the resultant effects on the sample. With the knowledge gained, the community has found...

Evaluation of EUV resist performance below 20nm CD using helium ion lithography

Evaluation of EUV resist performance below 20nm CD using helium ion lithography

For the introduction of EUV lithography, development of high performance EUV resists is of key importance. This development involves studies into resist sensitivity, resolving power and pattern uniformity. We have used a sub-nanometer-sized 30 keV helium ion beam to expose chemically amplified (CAR) EUV resists. There are similarities in the...

Novel nanosample preparation with a helium ion microscope

In this article, we present novel sample preparation methods using a helium ion microscope (HIM). We report the possibility of reshaping, at room temperature, thin metal lines on an electron-transparent membrane: A set of platinum bridges with standard geometry (300 × 200 × 15 nm) was modified at room temperature into different shapes using...

Localised plasma deposition of organosilicon layers on polymer substrates

Organosilicon coatings provide good optical and mechanical properties and are excellent candidates for the modification of the surface energy of polymers. These coatings can be deposited by plasma polymerization of hexamethyldisiloxane (HMDSO) under atmospheric pressure and at room temperature. The resulting films can range from soft,...

Is helium ion beam induced processing applicable to EUV mask repair?

Initiation of femtosecond laser machined ripples in steel observed by scanning helium ion microscopy (SHIM)

The physics of ablation has been studied experimentally with ultrashort laser pulses of 210 fs with a wavelength of 800 nm. A specimen of highly alloyed steel (alloy 800H) has been used. After the laser ablation experiments the surface has been inspected using SEM, AFM and scanning helium ion microscopy (SHIM). At the lowest fluence spherical...

Nanopillar growth by focused helium ion-beam-induced deposition

A 25 keV focused helium ion beam has been used to grow PtC nanopillars on a silicon substrate by beam-induced decomposition of a (CH₃) ₃Pt(C_PCH₃) precursor gas. The ion beam diameter was about 1 nm. The observed relatively high growth rates suggest that electronic excitation is the dominant mechanism...

Sub-10-nm nanolithography with a scanning helium beam

Scanning helium ion beam lithography is presented as a promising pattern definition technique for dense sub-10-nm structures. The powerful performance in terms of high resolution, high sensitivity, and a low proximity effect is demonstrated in a hydrogen silsesquioxane resist. © 2009 American Vacuum Society.

Degassing of 3H/3He, CFCs and SF6 by denitrification: Measurements and two-phase transport simulations

The production of N2 gas by denitrification may lead to the appearance of a gas phase below the water table prohibiting the conservative transport of tracer gases required for groundwater dating. We used a two-phase flow and transport model (STOMP) to study the reliability of 3H/3He, CFCs and SF6 as groundwater age tracers under agricultural...

Caprock and overburden processes in geological CO2 storage: An experimental study on sealing efficiency and mineral alterations

A comprehensive set of experimental and analytical methods has been used to characterise the sealing and fluid -transport properties of fine-grained (pelitic) sedimentary rocks under the pressure and temperature conditions of geological CO2 storage. The flow experiments were carried out on cylindrical sample plugs of 28.5 or 38 mm diameter and...

Modelling two-phase transport of 3H/3He

Degassing of groundwater by excess denitrification of agricultural pollution complicates the interpretation of 3H/3He data and hinders the estimation of travel times in nitrate pollution studies. In this study we used a two-phase flow and transport model (STOMP) to evaluate the method presented by Visser (2007a) to interpret degassed 3H/ 3He...

More than a feeling: Bringing touch into astronauts' spatial orientation

Data show that spatial orientation in microgravity differs from that on Earth possibly facilitating space motion sickness and degrading performance. As a technology demonstration, we developed a Tactile Orientation Awareness Support Tool (TOAST) consisting of a vest with 56 vibrators. TOAST presents an artificial gravity vector by a localised...

Dating degassed groundwater with 3H/3He

The production of gases in groundwater under contaminated locations by geochemical and biological processes is not uncommon. Degassing of these gases from groundwater and repartitioning of noble gases between water and gas phase distorts groundwater dating by 3H/3He. We observed noble gas concentrations below atmospheric equilibrium in 20 out of...

Demonstrating trend reversal of groundwater quality in relation to time of recharge determined by 3H/3He

Recent EU legislation is directed to reverse the upward trends in the concentrations of agricultural pollutants in groundwater. However, uncertainty of the groundwater travel time towards the screens of the groundwater quality monitoring networks complicates the demonstration of trend reversal. We investigated whether trend reversal can be...

Applicability of iTIRM for roughness reduction monitoring

The results obtained with iTIRM during polishing are presented. It is shown that iTIRM unites the working ranges of several other techniques where iTIRM can be used during production where the others can not. The applicable range of iTIRM is shown to be at least 1 um down to 0.1 nm rms.