Semiconductor bridge: A plasma generator for the ignition of explosives

Abstract

Small metal bridgewires are commonly used to ignite energetic powders such as pyrotechnics, propellants, and primary or secondary explosives. In this paper we describe a new means for igniting explosive materials using a semiconductor bridge (SCB). When driven with a short (20 μs), low-energy pulse (less than 3.5 mJ), the SCB produces a hot plasma that ignites explosives. The SCB, a heavily n-doped silicon film, typically 100 μm long by 380 μm wide by 2 μm thick, is 30 times smaller in volume than a conventional bridgewire. SCB devices produce a usable explosive output in a few tens of microseconds and operate at one-tenth the input energy of metal bridgewires. In spite of the low energies for ignition, SCB devices are explosively safe. We describe SCB processing and experiments evaluating SCB operation. Also discussed are the SCB vaporization process, plasma formation, optical spectra from the discharge, heat transfer mechanisms from the SCB to the explosive powders, and SCB device applications.

Возбуждение Взрывчатых Превращений В Энергонасыщенных Соединениях На Основе Нанопористого Кремния С Помощью Полупроводниковых Быстродействующих Ключей И Энерговыделяющих Элементов

“…В образовавшемся сгустке плазмы до-стигается высокая концентрация энергии. Температура плазмы по оценкам составляет ∼ 4500−5000 K [5], а скорость ее расширения достигает 2000−3000 m/s. Резкое повышение температуры и быстрое расширение приводят к возникновению высокого давления (на уровне нескольких GPa).…”

Light Effect in Semiconductor Bridge Plasma Ignition

“…Each of these studies concentrated on the SCB itself and assumed that ignition is produced by the heat generated by the SCB plasma. However, the effect of other types of energy in the SCB plasma have also been discussed in the literature [7][8][9]. Shock energy is thought to be of little importance because the expansion rate of gas products is much lower than the sound speed [7].…”

“…Shock energy is thought to be of little importance because the expansion rate of gas products is much lower than the sound speed [7]. Meanwhile, SCB plasma emission is thought to be involved in the process of ignition, but has not been evaluated in any detail [8]. In other cases of plasma ignition, heat is also considered to be the primary cause of ignition, based on experimental data [10] and numerical simulations [11].…”

Fabrication and Characteristics of Energetic Igniters Realized Through Sputtered Tantalum Nitride(TaN) Film Bridge

“…With the increasing demand for small ignition devices, investigation of heavily semiconductor or metallic film bridge, especially for doped polycrystalline silicon, titanium, platinum and chromium bridge, has attracted much attention in recent years [1][2][3][4][5][6][7]. Film ignition bridge devices, which are over 30 times smaller in volume, can function in a few tens of microseconds and operate at onetenth the input energy compared with the hot-wire devices while improving no-fire conditions and electrostatic safety.…”