Research On The Technique Of Micro Chip Exploding Foil Initiator And Planar Three Electrodes High Voltage Switch

Two kinds of micro chip exploding foil initiator(McEFI)was fabricated integrally through micro electromechanical system(MEMS)technology and low temperature co-fired ceramics(LTCC)technology in this paper.Additionally,a planar three electrode high voltage switch suitable for the exploding foil initiator system(EFIs)has been developed.The main contents and conclusions are as follows:(1).The McEFI was fabricated integrally through MEMS process.The velocity of multi-layer flyer was studied by Photonic Doppler Velometer(PDV).From the results of firing test,it can found that the velocity of the multi-layer flyer increases with the rise of the firing voltage.And under the same conditions of firing voltage,the reduction of the barrel diameter leads to the increase of the multi-layer flyer,which means that the maximum velocity of the multi-layer flyer can be obtained when the diameter of the barrel is equal to the width of the bridge foil.Moreover,the results of the detonation of ultrafine hexanitrostilbene(HNS)pellets indicate that the minimum firing voltage is 1.4kV,in the 0.22?F capacitor discharge condition.(2).The LTCC technology was used to produce McEFI.Under the condition of 0.22?F capacitor discharge,the velocity of ceramic flyer that accelerated by Au bridge foil increases first and then decreases with the increase of firing voltage.The maximum velocity of ceramic flyer is about 2422m/s at 2.50kV firing voltage.The results of the detonation of ultrafine hexanitrostilbene(HNS)pellets indicate that the minimum firing voltage of the Au bridge foil is 2.5kV and the minimum initiation voltage of Ag bridge foil is 2.8kV.(3).A planar three electrode high-voltage switch was designed according to the working mode of the traditional gas switch.The planar three electrode high voltage switch was prepared by directly etching the copper of printed circuit board(PCB)and using LTCC technology.From the research on performance of the switch,it can be inferred that there is a linear positive correlation between the self breakdown voltage(SBV)and the main electrode gap under the argon and the air atmosphere,while the shape of the electrode has little influence on the SBV.Besides,the switch delay time is the shortest when the working voltage is about 78%?92%of the self breakdown voltage.Additionally,the peak current and the delay time can be improved by the multi-arc switch in air compared with the single arc switch.The average inductance of the switch is 72 nH and the average resistance is 120 m?.Meanwhile.the performances of three kinds of switches are compared in the air environment.It can be concluded that the peak current,delay time,discharge cycle and inductance of the PCB switch and LTCC switch are better than those of commercial cold cathode trigger switch.