Micromachining. CERN Courier, Jul-Aug 1995, v. 35(5)

Full text: As well as making microcircuit components, X-ray lithography can also be used to make very small mechanical parts, either by using directly the exposed and developed photoresist, or as a mould to produce the component in another material such as ceramic or metal. In this revolutionary technology, metal components are made via the LIGA (Lithographic Galvanoformung und Abformung) technique in which the exposed and developed photoresist is coated with a conducting material and then electroplated, after which the resist is stripped away. In addition to fine size and precision resolution, X-rays offer the advantage of deep penetration and small scattering through the resist, so that patterns may be up to a millimetre deep, with very accurate straightness in directions parallel to the beam. Micromachining via LIGA was developed at KfK Karlsruhe; commercialization and further development is being vigorously pursued by the Institut fur Mikrotechnik in Mainz and by Microparts GmbH in Karlsruhe. Significant developments have been made at the Synchrotron Radiation Centre in Madison, Wisconsin, with new programmes start-ing at SRRC (Taiwan), CAMD (Baton Rouge, Louisiana), and LURE (Paris). There is now an active European Special Interest Group for LIGA. Commercially manufactured micromachines are starting to be used in sensors and connectors. The ability to integrate microdevices with microelectronics raises many interesting possibilities for the future, notably in medicine and for intelligent sensors. In all cases, however, widespread adoption will be governed by the ability to mass-produce cheaply, requiring high volume production. The high intensities of synchrotron radiation will assist in achieving these large throughputs