Second generation of optical IC-backside protection structure

摘要

In a system-on-chip (SoC) technology, the secret data such as cryptographic keys are stored on the chip. Accordingly, the system must be able to protect confidential data from unauthorized access. Despite the existence of numerous countermeasures that are implemented on the frontside of the chip, a lack of backside protection makes the integrated circuit (IC) vulnerable to physical and optical attacks. This paper aims to elaborate further on a backside protection structure that had proven as a valuable enhancement in the field of hardware security. The here presented second-generation of a backside protection mechanism provides solutions to increase the amount of monitoring data that can be used to monitor a backside attack. Through analyzing the obtained data by artificial intelligence (AI) approach, we can get detailed and accurate information about the IC backside and IC structures. Gaining this information helps to improve the protection mechanism. Furthermore, this study proposes to create a random roughness on the silicon back surface before coating a protection layer. A concept to use such an inhomogeneous surface in combination with the presented protection mechanism and its AI data to realization physical unclonable functions (PUF) is introduced, realizing a secure key generation or authentication.