Counterfeits and copies as a risk for safety-critical systems and economic assets

Copied chips are a problem for manufacturers and users. Manufacturers or design houses design innovative chips with a great deal of expertise and financial investment and suffer economic damage with every copy of these chips. Users cannot rely on the performance parameters of the originals when dealing with copies and therefore potentially risk the safety of their own products.

The copies are created in various ways: a chip can be “rebuilt” on the basis of the data sheet, i.e. a new chip design with approximately the same properties is created. If the circuits themselves are to be imitated, the chips are often analysed using various methods to reproduce the internal structure. In some cases, the chips are polished in small steps and photographed under a microscope and the layouts required for production are then redrawn using these images.

Validation of methods on systems of industrial partners

In the ARiS project, IMMS has researched methods to make this copying more difficult and thus protect chips against it. Two research directions were pursued: A watermark that can be used to mark original chips was investigated to prevent copying. As with banknotes, a check is incorporated to identify an original. Attacks, such as the delayering of chips, were also the focus of the work. A machine-learning-based attack model was developed at IMMS with which this reverse engineering process can be simulated. On this basis, circuit components can be found that are easy to copy and can be “hardened” in the next step. This involves using structures that are difficult to recognise. The investigated approaches to copy protection were successfully validated using various demonstrators.