AbstractAn innovative method for fabrication and rapid prototyping of high-aspect ratio micromechanical components in photoresist is discussed. The photoresist is an epoxy-negative-tone resist, called SU-8, which can be structured to more than 2mm in thickness by UV exposure. Small gears of 530m in diameter and 200m in thickness have been realized in this photoplastic and their functionality has been demonstrated. In addition a process called MIMOTECTM (MIcroMOlds TEChnology) has been established for the fabrication of metallic micromolds. MIMOTECTM is based on the use of the SU-8 spun on high thicknesses and electrodeposition of nickel. Thermoplastic microcomponents have been injected and mounted in watches.