近年來全球化的晶片產業鏈逐漸發展成熟，不同的產業聚落散佈在世界各地。雖然專業分工帶來更多的利益，但同時這種合作關係也會導致智慧財產(Intellectual Property, IP)暴露在危險之中，如何確保智慧財產不被竊取成為一個重要的議題。傳統的硬體模糊技術雖然能夠抵擋竊取硬體架構為目的的攻擊，但是硬體模糊技術本身需要改善所有相同設計的晶片使用同一組金鑰的問題，除此之外，針對硬體模糊技術而發明的滿足性攻擊(Satisfiability attack, SAT attack)能夠在短時間能破解出傳統的硬體模糊設計的金鑰，因此需要針對此攻擊研發新型態的硬體模糊技術。
本論文提出的使用硬體模糊技術之安全微型系統，只要付出有限的面積成本提升金鑰的長度就能大幅增加滿足性攻擊破解所需要的遞迴次數和耗時。金鑰的生產流程中，除了運用物理密鑰(Physical Unclonable Function, PUF)使每一個晶片都有自己獨一無二的金鑰組之外，也使用進階加密標準(Advanced Encryption Standard, AES)進行後處理，使物理密鑰的挑戰響應對不會因此而外洩，避免造成安全性的破口。系統的開機流程也經過設計，在安全模式下可以不受硬體模糊設計的影響，進行系統測試與物理密鑰的量測；在一般模式下，需輸入硬體模糊設計的金鑰，才能正確啟動。

In recent years, the global IC industry has gradually matured. Although the vertical international specialization brings more benefits, this kind of partnership will expose intellectual property (IP) to danger at the same time. Protecting the valuable IP becomes a serious problem. Using the conventional hardware obfuscation technology can prevent the IP from the hardware-based piracy, but the problem of using the same set of keys needs to be solved. Furthermore, the satisfiability attack against hardware obfuscation technology is invented. Therefore, a state-of-the-art hardware obfuscation technology solved the problem stated above is needed.
In this work, we proposed a satisfiability attack resilient physical unclonable function-based secure microsystem with hardware obfuscation. It increases the number of iterations and time needed for the satisfiability attack substantially with a limited area overhead. In the production process of the key, a chip using physical unclonable function (PUF) processes a unique set of keys. Furthermore, we can prevent the challenge-response pairs from leaking by using AES to encrypt as the post-processing. Also, the booting process has been re-designed to accommodate the hardware obfuscation. In secure mode, the measurement of system and PUF can be done without the activation of the hardware obfuscation. In normal mode, activating with the correct key of the hardware obfuscation is necessary to boot successfully.

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