Towards Blockchain-enabled Mask Writing for Security against Hardware Trojan Intrusion

Globalization of integrated circuits (ICs) may lead to the quality of ICs being compromised due to the possible untrusted entities involved in the supply chain. There have been well documented cases of chips secretly implanted with Trojans creeping into the supply chain. Studies have shown that tampering lithographic masks, also called as reticles, is one of the potential sources of hardware Trojan intrusion. This paper presents a novel blockchain-enabled mask writing technique to combat the alteration of the IC layout design at the mask making step. A blockchain-enabled file storage and transfer system for secure transfer of the layout GDSII file from the design house to the mask making machine is studied in this work. As part of this investigation, a smart contract is developed, which interacts with an external application programming interface (API) and fetches the design layout file from the file storage system. The smart contract developed as part of the research can be adopted in the existing EDA tools for mask making, curtailing the access sought by an adversary in the mask making process. The proposed smart contract is developed using Solidity language, on an online IDE called Remix. Finally, a case study is presented in this paper, validating the approach and simulating the proposed smart contract. The simulation of the smart contract is conducted on Goerli test network provided by Ethereum.