Electrostatic stepping micromotors have been designed with regard to low rotor friction on the axle. The design rules are determined using two-dimensional FEM calculations and taking into consideration the particular rotor position during motion. The motors are fabricated by a fully integrated LIGA process. The minimum driving voltages needed are measured to be about 60 V. Determination of the coefficients of friction in operation completes the rules for future designs.

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Moveable and flexible microstructures can be fabricated by a combination of the LIGA process and sacrificial layer techniques. A promising application of such flexible structures can be seen in the field of integrated optics, where the problem of precisely coupling fibers to integrated optical chips still demands a satisfactory solution. In the LIGA structure the fibers are guided by precisely positioned stop faces and then precisely located and prefixed by integrated spring elements. The fabrication of these spring-element arrays by the LIGA process has several advantages: the thermal expansion coefficient of the substrate can be matched to the optical chip material; the use of spring elements for prefixing simplifies the handling; and adhesives and related problems can be avoided. Additionally, a small center spacing of the fibers can be reached with a curved parabolic profile of the spring elements using the LIGA advantage of unrestricted design in the cross-sectional shape. First measurements of load deformation on the spring elements show that the values for the modulus of elasticity and for tensile strength found in literature for bulk nickel can be used for electrodeposited nickel too.

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The recent progress in the development of the lithographic processes within the LIGA technique is reported, which is based on deep-etch synchrotron radiation lithography, electroforming, and molding processes (in German: lithografie, galvanoformung, abformung). Mask blanks for high-contrast x-ray masks for 0.2 nm wavelength are fabricated from titanium and beryllium membranes produced by physical vapor deposition techniques. Absorber patterns on these masks can be produced by 50-keV electron-beam pattern generation in 3–5-μm-thick polymethylmethacrylate (PMMA) resists, because the use of beryllium strongly reduces the otherwise marked influence of electrons backscattered from the substrates on the resist profiles. To comply with the requirements of deep-etch lithography cross-linked PMMA resists and suitable multicomponent developers have been formulated. The casting resin-based resists are polymerized directly on the substrate which results in extremely low internal stresses to prevent stress corrosion of the resist structure during development.