Flash memory can be reverse engineered using x-ray technology. 1. If there is no specific mechanism to protect a chip against probing attacks, it is recommended to hide sensitive nets on lower metal...

Flash memory can be reverse engineered using x-ray technology.

1. If there is no specific mechanism to protect a chip against probing attacks, it is recommended to hide sensitive nets on lower metal layers, such as Metal 1 or Metal 2, to achieve more coverage from higher metal layers.