APPLICATIONS OF FLUOROCARBON POLYMERS IN MICROMECHANICS AND MICROMACHINING

Several thin-film deposition and etching techniques of the polymer flu orocarbon are investigated and the resulting thin-film properties will be compared with those of commercially available bulk polytetrafluoro ethylene. The most promising deposition technique is performed in a co nventional reactive ion etcher using a carbonhydrotrifluoride (CBF3) p lasma. By changing the deposition parameters, control of the propertie s and step coverage of the deposited thin films within a certain range is possible, eg., uni-directional and conformal step coverage of depo sited thin films can be obtained. Etching is performed with the help o f an evaporated aluminium oxide mask using an oxygen, nitrogen, or sul furhexafluoride plasma for isotropic etching, or a CHF3 plasma giving a directional etch profile. The combination of the unique properties, deposition and etching techniques make fluorocarbon thin films a promi sing tool for micromachining; a number of applications will be discuss ed and demonstrated.