Planar Trigger Switch and Its Integrated Chip With Exploding Foil Initiator Based on Low-Temperature Cofired Ceramic

Abstract

A planar trigger switch constituting of three electrodes was designed and fabricated using low-temperature cofired ceramic, and characterized under an atmospheric pressure. The results showed that when the operating voltage ranges between 77.2% and 86.8% of its self-breakdown voltage, the inductance of the switch was lower than that of commercial spark gap switch by approximately 60 nH, the current rising time was shortened by nearly 1/2, and the peak current increased by about 30%. The peak current and rising edge were 4000 A and 146 ns at 0.22 μF/2.0 kV, respectively, which was in agreement with simulation values well. Subsequently, the switch was devised to be in situ integrated with an exploding foil initiator together. The electrical characterizations were performed on the chip, obtaining the switch's rapid turn- on time of 29 ns and a large current density of $1.08 \times 10^{8}\,\text{A}\cdot \text{cm}^{-2}$ at 0.22 μF/2.25 kV. Furthermore, photon Doppler velocimetry was exploited to capture the detailed trajectory of a 50-μm-thick flyer with an extracted terminal velocity of 2200 m/s. Finally, boron–potassium nitrate pellets and hexanitrostilbene pellets were used to successfully verify the practicability of the chip in the ignition and detonation of explosives.