High-vacuum evaporation

Technological developments in high vacuum evaporation techniques have been responsible for the rapid growth of the domestic citrus industry. These techniques were developed and refined, for the most part, during World War II and they made possible the manufacture and production of many perishable foods and medicines. Most notable for the domestic citrus industry was the development of frozen concentrated citrus juices which was made possible by the development of these high vacuum evaporators... 

Platinum-shadowed replicas of freeze-fractured samples were prepared in a Denton Vacuum DFE-3 with a Denton DV-502 High-Vacuum Evaporator. An electron microscope Hitachi HU-11A with an optimum resolution of 7 A was used to observe and photograph the replicas. 

The model catalysts were prepared by HV deposition of an amorphous SiO film (by evaporation of SiO in 10 Pa of oxygen), onto which Pt was deposited by high vacuum evaporation, as described earlier (7). In order to get catalysts of different dispersion, the mean thickness of deposited Pt was varied between 0.1 and 1 nm. By TEM inspection of catalyst specimens the particle density and the particle size distribution were obtained, from which data the platinum surface area and the dispersion were calculated. Additionally a conventional 6,3 % Pt/Sio catalyst (EUROPT-1, d = 1.7 nm) was used in the experiments. 

A Pt layer was deposited by means of high vacuum evaporation, patterned via a lift-off process and insulated with PECVD silicon nitride. The working electrodes... 

Fig. 1. Plot of pressure increase against time for an experiment at 189.2° on 31.3 mg. of high-vacuum evaporated nickel with 14.9 mm. of formic acid initially., Experimental data, koS = 0.0615 mm. sec. , Calculated from Equation (1), K = 2.52, fcoS = 0.0740 mm. sec. (g). Calculated from Equation (2), K = 0.72, koS = 0.0646 mm. sec. O, Calculated from Equation (3), a = 50 sec., fcoS = 0.0767 mm. sec." ...

OPTICAL PROPERTIES OF HIGH VACUUM EVAPORATED FLUORIDE FILMS [192]... 

In solutions of [(M6Cli2)Cl2(H20)4]-4H20 in aliphatic alcohols the concentration of the different water-aleohol species is a function of the water/alcohol molar ratio in the solution. To increase the concentration of species rich in coordinated alcohol molecules it is necessary to reduee the amount of water in the solution. This can be achieved by high-vacuum evaporation of the solutions and by drying the remaining solids under vacuum. After this proeedure the amount of water in the system is only partly reduced. The alcohol is vacuum distilled once more. Repeating the distillation-evaporation and drying process under vacuum minimizes the amount of water... 

On the other hand, PVD involves purely physical processes, such as high-vacuum evaporation or plasma sputter bombardment, in which material is released fi om a source and transferred to the substrate. In thermal evaporation, the source material is... 

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