Fabrication of photoplastic high-aspect ratio microparts and micromolds usina SU-8 UV resist

Abstract

An innovative method for fabrication and rapid prototyping of high-aspect ratio micromechanical components in photoresist is discussed. The photoresist is an epoxynegative-tone resist, called SU-8, which can be structured to more than 2 mm in thickness by UV exposure. Small gears of 530 μm in diameter and 200 μm in thickness have been realized in this photoplastic and their functionality has been demonstrated. In addition a process called MIMOTEC™ (MIcroMOlds TEChnology) has been established for the fabrication of metallic micromolds. MIMOTEC™ 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.