Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2001 · 11 citations · 0 references
EngineeringMaterials EngineeringMaterials ScienceMechanical Behavior Of MaterialsMicroelectromechanical SystemsMicrofabricationMems FabricationMems MaterialsMicrofabrication MaterialsMicrofabrication ProcessesMicromachiningMicrostructure ControlEtchingFriction CoefficientHardnessMicroelectromechanical System FabricationReactive Ion EtchingSeeding Strategies
Ultrananocrystalline diamond (UNCD) with grain sizes in the range of 2 - 5 nm is produced using a microwave plasma chemical vapor deposition process with argon-rich C<SUB>60</SUB> or CH<SUB>4</SUB> plasmas. This material has excellent mechanical properties: high hardness and Young modulus, and an extremely low friction coefficient (approximately 0.01). It is resistant to chemical attack, and is potentially biocompatible. These properties make UNCD a very good candidate for a diamond-based microelectromechanical systems (MEMS) technology. We report on the micromachinability of this material by selective seeding, selective growth and reactive ion etching, in conjunction with SiO<SUB>2</SUB> sacrificial layers for fabricating 3-D structures with freestanding or movable parts. These micromachining techniques are used to develop a totally UNCD-made turbine as a demonstration for UNCD-based MEMS.