LIGA
The German acronym LIGA stands for LIthographie, Galvanik, Abformung – lithography, galvanics, moulding. The process was developed around 30 years ago at the then Nuclear Research Centre and is suitable for the production of ultra-fine structures and micromechanical components. The structure distances can be approx. 0.2 µm minimum, the structure heights up to several millimetres. A height:width ratio of the structures (aspect ratio) of more than 50 can be achieved. The process is used for example in precision optics or in the manufacture of minute mechanical components such as gear wheels for micromechanical transmissions. The components can be made of different synthetics, metals or ceramics. Various steps of the LIGA method are analogous to the photolithography process used in PCB manufacture.