The rational design of a Au(I) precursor for focused electron beam induced deposition

Au(I) complexes are studied as precursors for focused electron beam induced processing (FEBIP). FEBIP is an advanced direct-write technique for nanometer-scale chemical synthesis. The stability and volatility of the complexes are characterized to design an improved precursor for pure Au deposition. Aurophilic interactions are found to play a key role. The short lifetime of ClAuCO in vacuum is explained by strong, destabilizing Au–Au interactions in the solid phase. While aurophilic interactions do not affect the stability of ClAuPMe3, they leave the complex non-volatile. Comparison of crystal structures of ClAuPMe3 and MeAuPMe3 shows that Au–Au interactions are much weaker or partially even absent for the latter structure. This explains its high volatility. However, MeAuPMe3 dissociates unfavorably during FEBIP, making it an unsuitable precursor. The study shows that Me groups reduce aurophilic interactions, compared to Cl groups, which we attribute to electronic rather than steric effects. Therefore we propose MeAuCO as a potential FEBIP precursor. It is expected to have weak Au–Au interactions, making it volatile. It is stable enough to act as a volatile source for Au deposition, being stabilized by 6.5 kcal/mol. Finally, MeAuCO is likely to dissociate in a single step to pure Au.

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Atomic Layer Deposition and Vapor Deposited SAMS in a CrossBeam FIB-SEM Platform: A Path To Advanced Materials Synthesis

Microscopy Today ◽

10.1017/s1551929500054444 ◽

2009 ◽

Vol 17 (2) ◽

pp. 18-25

Author(s):

E. L. Principe ◽

Cheryl Hartfield ◽

Rocky Kruger ◽

Aaron Smith ◽

Ray Dubois ◽

...

Keyword(s):

Electron Beam ◽

Ion Beam ◽

Three Dimensional ◽

Target Material ◽

Chemical Vapor ◽

Ion Beams ◽

Two Dimensions ◽

Nanometer Scale ◽

Direct Write ◽

Etch Pattern

Nanopatterning refers to the fabrication of nanometer-scale structures, meaning patterns with at least one lateral dimension between the size of an individual atom and approximately 100 nm. Direct Write or Maskless Lithography as discussed in this article refers to the use of a focused beam, either an ion beam or an electron beam, to create a patterned image directly into (etch), or on top of (deposition), the target material. Both electron beams and ion beams can be used together with gas injection technology to deposit three dimensional structures on the nanometer scale through the process of either electron beam assisted or ion beam assisted chemical vapor deposition (CVD). The deposition occurs only in the vicinity where the electron beam or ion beam is being scanned. Therefore, the deposit will follow the form of the scanned beam in two dimensions. This approach can be applied to produce three-dimensional objects by successively layering upon the two-dimensional pattern. In the case of ion beams in particular, the direct write process can also produce an etch pattern on the nanometer scale as the ion beam physically mills away the material via ion bombardment. This process can also be chemically enhanced for certain materials such as simultaneous use of water to selectively etch carbon.

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Electron-driven and thermal chemistry during water-assisted purification of platinum nanomaterials generated by electron beam induced deposition

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.10 ◽

2018 ◽

Vol 9 ◽

pp. 77-90 ◽

Cited By ~ 5

Author(s):

Ziyan Warneke ◽

Markus Rohdenburg ◽

Jonas Warneke ◽

Janina Kopyra ◽

Petra Swiderek

Keyword(s):

Electron Beam ◽

Direct Write ◽

Reaction Products ◽

Thermal Desorption Spectrometry ◽

Thermal Chemistry ◽

Volatile Products ◽

Versatile Tool ◽

Electron Beam Induced Deposition ◽

Electron Stimulated Desorption ◽

The Stability

Focused electron beam induced deposition (FEBID) is a versatile tool for the direct-write fabrication of nanostructures on surfaces. However, FEBID nanostructures are usually highly contaminated by carbon originating from the precursor used in the process. Recently, it was shown that platinum nanostructures produced by FEBID can be efficiently purified by electron irradiation in the presence of water. If such processes can be transferred to FEBID deposits produced from other carbon-containing precursors, a new general approach to the generation of pure metallic nanostructures could be implemented. Therefore this study aims to understand the chemical reactions that are fundamental to the water-assisted purification of platinum FEBID deposits generated from trimethyl(methylcyclopentadienyl)platinum(IV) (MeCpPtMe3). The experiments performed under ultrahigh vacuum conditions apply a combination of different desorption experiments coupled with mass spectrometry to analyse reaction products. Electron-stimulated desorption monitors species that leave the surface during electron exposure while post-irradiation thermal desorption spectrometry reveals products that evolve during subsequent thermal treatment. In addition, desorption of volatile products was also observed when a deposit produced by electron exposure was subsequently brought into contact with water. The results distinguish between contributions of thermal chemistry, direct chemistry between water and the deposit, and electron-induced reactions that all contribute to the purification process. We discuss reaction kinetics for the main volatile products CO and CH4 to obtain mechanistic information. The results provide novel insights into the chemistry that occurs during purification of FEBID nanostructures with implications also for the stability of the carbonaceous matrix of nanogranular FEBID materials under humid conditions.

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Direct-write Electron Beam Lithography: History and State of the Art

MRS Proceedings ◽

10.1557/proc-584-33 ◽

1999 ◽

Vol 584 ◽

Cited By ~ 5

Author(s):

Dustin W. Carr ◽

Richard C. Tiberio

Keyword(s):

Electron Beam ◽

Electron Beam Lithography ◽

System Integration ◽

High Sensitivity ◽

Spot Size ◽

Direct Write ◽

Electron Sources ◽

Control Electronics ◽

Electron Microscopes ◽

The Stability

AbstractDirect-write electron beam lithography is a patterning technique that has rapidly evolved over the last 40 years. For many years it has been possible to use electrons to pattern lines with widths as narrow as 10 rum. Recent advances in resist materials, electron sources, and system integration have further enhanced the capabilities. High-sensitivity resists provide substantial increases in the throughput without sacrificing resolution. Thermal field-emission sources improve the stability and reduce the minimum attainable spot size. Modem lithography systems integrate the electron beam column with advanced control electronics, making a system capable of nanometer-scale placement accuracy. In addition to these improvements, the technology is more accessible now than ever before, thanks to the proliferation of lithography systems consisting of modified scanning electron microscopes.

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TEM characterization of Au/Polysilicon interactions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100176381 ◽

1990 ◽

Vol 48 (4) ◽

pp. 650-651

Author(s):

N. David Theodore ◽

Leslie H. Allen ◽

C. Barry Carter ◽

James W. Mayer

Keyword(s):

Solid Phase ◽

Single Crystal Silicon ◽

Chemical Vapor ◽

Electrical Contacts ◽

Silicon Substrates ◽

Crystal Silicon ◽

Transmission Electron ◽

Polysilicon Films ◽

The Stability

Metal/polysilicon investigations contribute to an understanding of issues relevant to the stability of electrical contacts in semiconductor devices. These investigations also contribute to an understanding of Si lateral solid-phase epitactic growth. Metals such as Au, Al and Ag form eutectics with Si. reactions in these metal/polysilicon systems lead to the formation of large-grain silicon. Of these systems, the Al/polysilicon system has been most extensively studied. In this study, the behavior upon thermal annealing of Au/polysilicon bilayers is investigated using cross-section transmission electron microscopy (XTEM). The unique feature of this system is that silicon grain-growth occurs at particularly low temperatures ∽300°C).Gold/polysilicon bilayers were fabricated on thermally oxidized single-crystal silicon substrates. Lowpressure chemical vapor deposition (LPCVD) at 620°C was used to obtain 100 to 400 nm polysilicon films. The surface of the polysilicon was cleaned with a buffered hydrofluoric acid solution. Gold was then thermally evaporated onto the samples.

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ELECTRON BEAM DIRECT WRITE EFFECTS ON CMOS DEVICES

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1988460 ◽

1988 ◽

Vol 49 (C4) ◽

pp. C4-291-C4-294

Author(s):

K. BARLOW

Keyword(s):

Electron Beam ◽

Direct Write

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Review of Development and Performance Evaluation of Active-matrix Nanocrystalline Si Electron Emitter Array for Massively Parallel Electron Beam Direct-write Lithography

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.135.221 ◽

2015 ◽

Vol 135 (6) ◽

pp. 221-229

Author(s):

Naokatsu Ikegami ◽

Akira Kojima ◽

Hiroshi Miyaguchi ◽

Takashi Yoshida ◽

Shinya Yoshida ◽

...

Keyword(s):

Electron Beam ◽

Performance Evaluation ◽

Massively Parallel ◽

Direct Write ◽

Active Matrix ◽

Electron Emitter ◽

Emitter Array ◽

And Performance ◽

Nanocrystalline Si

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The influence of the Stokes and Archimedes forces on the stability of a two-phase flow

Proceedings of the Mavlyutov Institute of Mechanics ◽

10.21662/uim2003.1.020 ◽

2003 ◽

Vol 3 ◽

pp. 266-270

Author(s):

B.H. Khudjuyerov ◽

I.A. Chuliev

Keyword(s):

Spectral Method ◽

Stability Region ◽

Gas Flow ◽

Two Phase Flow ◽

Solid Phase ◽

Stability Characteristic ◽

Phase Flow ◽

Two Phase ◽

The Stability

The problem of the stability of a two-phase flow is considered. The solution of the stability equations is performed by the spectral method using polynomials of Chebyshev. A decrease in the stability region gas flow with the addition of particles of the solid phase. The analysis influence on the stability characteristic of Stokes and Archimedes forces.

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Expanding 3D Nanoprinting Performance by Blurring the Electron Beam

Micromachines ◽

10.3390/mi12020115 ◽

2021 ◽

Vol 12 (2) ◽

pp. 115

Author(s):

Lukas Seewald ◽

Robert Winkler ◽

Gerald Kothleitner ◽

Harald Plank

Keyword(s):

Electron Beam ◽

Direct Write ◽

Design Flexibility ◽

Individual Branch ◽

Inclination Angles ◽

3D Architecture ◽

20 Nm ◽

Surface Morphologies ◽

Nm Range ◽

Mechanical Rigidity

Additive, direct-write manufacturing via a focused electron beam has evolved into a reliable 3D nanoprinting technology in recent years. Aside from low demands on substrate materials and surface morphologies, this technology allows the fabrication of freestanding, 3D architectures with feature sizes down to the sub-20 nm range. While indispensably needed for some concepts (e.g., 3D nano-plasmonics), the final applications can also be limited due to low mechanical rigidity, and thermal- or electric conductivities. To optimize these properties, without changing the overall 3D architecture, a controlled method for tuning individual branch diameters is desirable. Following this motivation, here, we introduce on-purpose beam blurring for controlled upward scaling and study the behavior at different inclination angles. The study reveals a massive boost in growth efficiencies up to a factor of five and the strong delay of unwanted proximal growth. In doing so, this work expands the design flexibility of this technology.

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