It is very difficult to classify the targets by methods to be used for their preparation. The choice of the method depends on many parameters such as chemical or physical form of the starting material, the type of target (e.g. self-supporting or backed), or the target thickness. This makes it difficult to make any rough indication which production technique is the most suitable for a specific target.
The method should not only be effective i.e. assure the production of the final target with the required characteristic, but as well it should be efficient in terms of minimising the material costs, especially when an expensive enriched isotopic material is used. To optimise the usage of such a material the method is initially developed or tested with natural one. However, it is necessary to keep in mind that the isotopic material may behave differently.
In general the methods applied for target preparation can be roughly classified as mechanical, physical and chemical.
Mechanical reshaping and powder processing:
– cold rolling,
– powder compacting (including sedimentation and sintering),
Physical:
– vapour condensation where material to be deposited can be heated by: resistant heating, electron bombardment (electron beam gun),
– levitation heating and melting,
– ion beam sputtering,
– HIVIPP (HIgh energy VIbrational Powder Plating);
– electrospraying,
Chemical:
– electrodeposition,
– thermal cracking,
– polymerisation.