Reverse Blocking Diode Thyristor With High Di/Dt Capability for Explosive Foil Initiator Applications

Abstract

High-voltage switch with high current and high current rise rate capability is important in explosive foil initiator (EFI) applications because the current with high amplitude and short rise time is necessary in order to gasify the explosive foil. In this work, reverse blocking diode thyristor (RBDT) for this application is optimally designed and fabricated. The 2-D numerical model of RBDT is first established. Based on this model, the cathode layout and the doping concentration of P base layer of the device are carefully analyzed. The cell size and the length ratio of the emitter to the short-circuit point at cathode are analyzed. Samples of RBDT are developed in our laboratory, with the blocking voltage of 1600 V. The peak current of 2400 A is acquired in the pulse discharge experiment, with a maximum current rise rate as high as 18 kA/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{s}$ </tex-math></inline-formula> , which is the highest <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{d}{i}/\text{d}{t}$ </tex-math></inline-formula> value reported for RBDT until now. This result makes the proposed RBDT a promising candidate for EFI applications.