UCL in the News: Mobile phone SIM cards can take the heat

The subscriber identity module (SIM) card is the heart of a mobile phone, providing a record of numbers received, numbers dialled and text messages. …

In an unusual investigation, electronic engineers Benjamin Jones and Tony Kenyon [UCL Electronic & Electrical Engineering] subjected SIM cards to trial by heat. …

Using acid, the researchers gently stripped the protective epoxy moulding surrounding each chip in order to expose its circuitry.

The cards were then placed in heated air for 10 minutes, were allowed to cool and the researchers then sought to recover data by attaching tiny probes to the circuit and reading its contents via an interface pad. …

Jones and Kenyon say the experiment proves that SIM cards can survive to 450 C - and quite possibly beyond that. …

"A chip that has been exposed to such temperatures may also be mechanically damaged, and the data may not be retrieved by simple probing or rewiring. But the data itself remains uncompromised and can possibly be read using other techniques," say Jones and Kenyon.

Their paper appears in the latest issue of the journal Forensic Science International.