Metal–interlayer–metal structured initiator containing Al/CuO reactive multilayer films that exhibits improved ignition properties

Abstract

Aluminum/cupric oxide (Al/CuO) reactive multilayer films (RMFs) are widely used for micro-chip energetic initiator applications; however, there are only a few examples where they are initiated through the direct input of electrical energy. This study describes the preparation of micro-chip energetic initiators containing Al/CuO RMFs as an interlayer between two Al electrical contact pads that are prepared using an image reversal lift-off process and the magnetron sputtering technology. This design enables the direct transfer of current from the contact pads to Al/CuO RMFs, which results in fast ignition (less than 1.0 μs) and produces luminous flame ball that spread over a wide area (maximum flame area of 13.8 mm2). A metal–interlayer–metal (MIM) structured initiator will not be fired until the external voltage has exceeded the breakdown field strength of CuO layers. These initiators achieved a critical breakdown voltage (VB) of 32–50 V and a complete electrical-explosion voltage (VC) of 72–84 V. The ignition threshold rises with increasing the bilayer thicknesses of the RMFs. These characteristics of this specially structured initiator are well suited for applications in highly efficient and insensitive initiating explosive devices.