Some recent advances in multi-material micro- and nano-manufacturing

The increasing demand for micro-products and components can be met only partly by the lithography-based micro-electromechanical systems fabrication processes that originated from the silicon-based microelectronics revolution of the late twentieth century. In particular, such processes have limitations when applied to new micro-devices which require the use of a variety of materials and complex 3D microstructures with high aspect ratios. In this context, the paper presents technologies complementary to lithography-based processes for the manufacture of devices or components incorporating micro- and nano-scale features. More specifically, special attention is given to the main findings obtained over the last 5 years from the authors' research programme on a range of micro- and nano-manufacturing technologies, namely, micro-electrodischarge machining, laser ablation, micro-milling, focussed-ion beam machining, micro-injection moulding, nano-imprint lithography, hot embossing and electroforming.