Vacuum arc evaporation

Cyviene, J., Laurikaitis, M., and Dudonis, J., Deposition of nanocomposite Zr-ZiOj films by reactive cathodic vacuum arc evaporation. Mater. Sci. Eng. B 118 (2005) 238-241. 

C. Gautier, H. Moussaoui, F. Elstner and J. Machet, Comparative study of mechanical and structural properties of CrN films deposited by d.c. magnetron sputtering and vacuum arc evaporation. Surf Coat. Technol. 1996, 86-87, 254-262. 

The fullerenes, Cgo and C70, are produced in the laboratory by the contact arc-evaporation of 6 mm graphite rods (e.g. Johnson Matthey, spectroscopic grade) in 100 torr of helium in a water-cooled stainless steel chamber described previously [5]. The soluble material in the soot produced from the arc-evaporation is extracted with toluene using a Soxhlet apparatus. The pure fullerenes are obtained by chromatography on neutral alumina columns using hexanes as the eluant, or by the use of a simple filtration technique using charcoal-silica as the stationary phase and toluene as the eluant [5]. The fullerenes so prepared are characterized by UV/Vis spectroscopy and other techniques. FT-IR spectra of vacuum deposited fullerene films on KBr crystals also provide a means of characterization, just as do Raman spectra of films deposited on a silicon crystal. Ultraviolet and X-ray photoelectron spectra of fullerene films on... 

A solution of 5 mmol of azido alkene in 5 mL of CII2C12 in a dry two-neckcd flask under Ar is cooled to 0°C, then 1.07 g (5.5 mmol) of thexylchloroborane-dimethyl sulfide complex are added slowly and the mixture is stirred for 4 h at r.t. Then 1 mL ol CH3OH is added and the mixture is further stirred for 10 min, the solvents arc evaporated under vacuum, and the residue is taken up in 10 mL of Et20. The amine hydrochloride is extracted with two 10-inL portions of 1 M HCl, then H20 is distilled under vacuum. The crystallized amine hydrochloride is purified by recrystallization. The free amine can be obtained by basic treatment and extraction with solvent. 

Vacuum arcs. This type of low-pressure arc, operating with cathode spots, is special because the gas-phase working fluid is provided by erosion and evaporation of the electrode material. This type of arc is of importance in high-current electrical equipment, high-current vacuum circuit breakers, and switches. 

T. Miyata, S. Tsukada, T. Minami, Preparation of anatase Ti02 thin films by vacuum arc plasma evaporation . Thin Solid Eilms, 496, 136-140, (2006). 

The main categories of PVD processing are vacuum deposition (evaporation), sputter deposition, arc vapor deposition, and ion plating, as depicted in Figure 1.1. 

Arc vaporization The vaporization of a solid (cathodic) or liquid (anodic) electrode material using a vacuum or gaseous arc. Characterized by high ionization of the vaporized material. Also called Arc evaporation. 

ZnO films can be prepared by many techniques, including chemical vapour deposition (CVD) [135], electron beam evaporation [136], molecular beam epitaxy (MBE) [137], pulsed laser deposition (PLD) [138], sol-gel [139], spray pyrolysis [140], sputtering [141] and chemical bath deposition [142]. Thermal oxidation of metallic Zn [143-149], ZnS or ZnSe [150-153] films has been used to prepare ZnO films. The Zn precursor films were deposited onto the substrates (glass, sapphire or Si) by magnetron sputtering, thermal/ electron-beam evaporation or filtered cathodic vacuum arc technique. Oxidation treatment was normally conducted in air or oxygen atmospheres in a wide temperature range typically from 300 to 1000°C. 

When 5.00 mL of ether has been delivered by the syringe pump, the pump is shut off The reactor is allowed to run an additional 15 min before the fluorine and the mercury arcs ate shut off. The preaerosol furnace, the evaporator heater unit, and the coolant pump are shut off. Once the system approaches ambient conditions, all the helium carriers are shut off and the product trap valves are closed The product trap and its Dewar flask filled with liquid nitrogen are removed to the vacuum line where the trap is evacuated... 

Principles Procedure and plant involved are similar to those used for vacuum evaporation. The pressure of the coating-chamber atmosphere, which may be air or an inert gas, is reduced and an arc is struck. The M vapour formed subsequently deposits on surrounding cool surfaces, including those of A/j. 

Features The rate of deposition is low compared with that of vacuum evaporation, and is affected by variables such as pressure and temperature of coating-chamber atmosphere, arc voltage, cathode current density and geometry of cathode and A/j. A high vacuum is not essential, particularly where an inert gas can be used. The A/, disintegration rate is affected by the atomic weight of coating-chamber gas. 

In Section 13.2, we introduce the materials used in OLEDs. The most obvious classification of the organic materials used in OLEDs is small molecule versus polymer. This distinction relates more to the processing methods used than to the basic principles of operation of the final device. Small molecule materials are typically coated by thermal evaporation in vacuum, whereas polymers are usually spin-coated from solution. Vacuum evaporation lends itself to easy coaling of successive layers. With solution processing, one must consider the compatibility of each layer with the solvents used for coating subsequent layers. Increasingly, multilayered polymer devices arc being described in the literature and, naturally, hybrid devices with layers of both polymer and small molecule have been made. 

On a commercial scale, hexamine is manufactured from anhydrous NHi and a 45% solution of methanol-free formaldehyde. These raw materials, plus recycle mother liquor, arc charged continuously ai carefully controlled rates 10 a high-velocity reactor. Tile reaction is exothermic. "Die reactor effluent is discharged into a vacuum evaporator which also serves as a... 

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