Localized etching of polymer films using an atmospheric pressure air microplasma jet

摘要

A direct-write process device based on the atmospheric pressure air microplasma jet (A mu PJ) has been developed for the localized etching of polymer films. The plasma was generated by the air discharge ejected out through a tip-nozzle (inner diameter of 100 mu m), forming the microplasma jet. The A mu PJ was capable of reacting with the polymer surface since it contains a high concentration of oxygen reactive species and thus resulted in the selective removal of polymer films. The experimental results demonstrated that the A mu PJ could fabricate different microstructures on a parylene-C film without using any masks or causing any heat damage. The etch rate of parylene-C reached 5.1 mu m min(-1) and microstructures of different depth and width could also be realized by controlling two process parameters, namely, the etching time and the distance between the nozzle and the substrate. In addition, combining XPS analysis and oxygen-induced chemical etching principles, the potential etching mechanism of parylene-C by the A mu PJ was investigated. Aside from the etching of parylene-C, micro-holes on the photoresist and polyimide film were successfully created by the A mu PJ. In summary, maskless pattern etching of polymer films could be achieved using this A mu PJ.