| Abstrakt: |
A low-cost HARMS (High Aspect Ratio MicroSystems) process has been developed, which enables the fabrication of micromechanical parts or entire systems of metal. In comparison with the original LIGA process, this process is a truly low-cost one. Based on a state-of-the-art mask technique. UV-sensitive polymer and a self-built spray processor for resist development, structures with heights of 300 μm, lateral dimension of 30 μm, sharp sidewalls and aspect ratios up to 10 can be achieved. The developed moulds can be filled with metais (Ni, Cu) using electroforming. A proper control over some plating-bath parameters is imperative when no defects are allowed. Especially for a nickel(II)-sulfamate bath, temperature, particle filtration, periodic active carbon filtration of degenerated organics, pH measurement and monitoring of the nickel concentration are required. Monitoring the surface-active agent concentration is of great importance. Potentiometric tilration using a new tenside electrode allows determination of the agent and its decomposition products. Examples of gearwheels and planar coils in photoresist and metal are given. |
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