Microsystems Technology

Metal Surface Micromachining


Metal surface micromachining is an alternative way to build up complete MEMS systems or a part of them. By using mainly electroplating and lithography in combination with PVD, PECVD and etching processes it is possible to fit the requirements for a variety of applications. The low CMOS/ASIC compatible temperature budget makes this process suitable for the monolithical integration of a complete MEMS system. Additional a high flexibility in design and thickness is given.

Application areas

• Monolithical integration, post-CMOS/ASIC compatible processing
• Electrodes for electrostatic actuation/deflection
• Bondframes for wafer level packaging, eutectic AuSi, AuSn
• RF MEMS switches
• Metal wiring
• Bondpads, bumps
• High-Q inductors
• …

Realised applications

• Deflection device for projection maskless lithography PML2, CMOS post processed 
• Micromirror array for IR imaging, CMOS post processed 
• High precision capacitors
• RF MEMS device
• Wafer level packaging
• 3D shaped metal structures
• Bistable thermal micro relay

Process environment

• Electroplating: gold, nickel, copper, tin, up to 60µm thickness
• Lithography: contact/stepper, thin and thick resist processes from 1µm to 70µm, spin or spray coated, resolution down to 0.8µm, aspect ratio up to 10
• PECVD: nitride, oxide
• PVD: evaporation, sputtering (seed-, barrier layer, …)
• Etching: RIE, DRIE, wetetching, spinetching