A fabrication process of the net shape 316-L stainless-steel micro machine components is reported. The fabrication process combines softlithography and powder metallurgy to produce microcomponents of complex geometries of high quality. The process starts with softlithography by producing ultra thick SU-8 master moulds and their negative replicas of polydimethylsiloxane (PDMS). Then stainless-steel slurry is prepared by mixing super fine 316-L steel powder and binder to fill the PDMS moulds. The two binders used in the experiments were Duramax D-3005 and a mixture of B1000 and B1007. The PDMS micro moulds are filled with the metallic slurries and green parts are obtained from de-moulding, before going through de-binding and sintering in forming gas atmosphere. The fabrication steps were repeatedly tested. The resultant micro parts show high quality shape retention which is attributed to the quality of the SU-8 master moulds. The hardness property of the sintered microcomponents was tested with a micro indenter and a 200 g load was applied. The Vickers hardness of the sintered components was found to be about 255, which was higher than 225 of annealed 316L stainless steel and the two binders make little difference on the hardness of the sintered samples.

In spite of significant improvements in micro-replication techniques, methods to fabricate well-defined net shape microstructures are still in a developing stage. Soft-lithography has the capability to manufacture complex micro-and nanostructures. Although it is considered a robust technique, a major limitation is related to the distortion encountered in the fabricated structures during the drying process. In the present work, a manufacturing technology has been developed that emerges the benefits of Soft-Lithography and Micro Electrical Discharge Machining (µ-EDM) to produce stainless steel precise micro-components for Microimplantable devices. The micro-parts produced by Soft-lithography were subsequently surface processed via µ-EDM in order to improve the surface quality. In addition to this, it was found that µ-EDM drastically improved the surface roughness of stainless steel microcomponents from Ra=3.4 µm to Ra =0.43 µm.

Ceramic materials are increasingly used in micro-electro-mechanical systems (MEMS) as they offer many advantages such as high-temperature resistance, high wear resistance, low density, and favourable mechanical and chemical properties at elevated temperature. However, with the emerging of additive manufacturing, the use of ceramics for functional and structural MEMS raises new opportunities and challenges. This paper provides an extensive review of the manufacturing processes used for ceramic-based MEMS, including additive and conventional manufacturing technologies. The review covers the micro-fabrication techniques of ceramics with the focus on their operating principles, main features, and processed materials. Challenges that need to be addressed in applying additive technologies in MEMS include ceramic printing on wafers, post-processing at the micro-level, resolution, and quality control. The paper also sheds light on the new possibilities of ceramic additive micro-fabrication and their potential applications, which indicates a promising future.