When it comes to electronics, we put a great deal of effort into constructing chips and circuits, but very little thought goes into deconstructing them. The quite-literal mountains of electronics waste that we generate, and subsequently ship to developing countries for pseudo-disposal, are a testament to that. That’s obviously a vexing issue, but so is the safe destruction of circuits and their data.
It’s a common scenario in espionage-oriented fiction: a character is working feverishly on hacking some database, when suddenly the bad guys show up. The character then throws their hard drives in the microwave to destroy the evidence—or simply sets their equipment on fire (for some reason). It would certainly be more convenient if they could just push a button, causing the electronics to destroy themselves.
That scenario isn’t just fiction—there are a number reasons why a self-destruct feature would be useful in the real world, and not just for spies and hackers. And, engineers from Cornell University have developed a mechanism for vaporizing those chips and circuits safely. Their method uses a polycarbonate shell to contain the circuit, along with rubidium and sodium biflouride in tiny cavities.
When self-destruction is desired, an RF signal can open microscopic graphene-on-nitride valves to mix those chemicals. The rubidium oxidizes quickly and releases heat to destroy the polycarbonate shell, and to break down the sodium biflouride. That then creates hydrofluoric acid to dissolve the circuit. That kind of technology would be very useful to entities like DARPA—who partially funded the research.