憶阻器被認為是用來替代未來非揮發性記憶體的一種非揮發性裝置。對於憶阻器記憶體而言，需要有參考電流來區分高阻抗和低阻抗。因此參考電流對於憶阻器的良率和可靠度有很大的衝擊，所以參考電流的設置是非常重要的。如果我們可以找到高阻抗跟低阻抗的邊界電流，我們就可以設置更佳的參考電流。因此，我們需要有可找到邊界電流的有效方法。

在這篇論文當中，我們提出一個測試方法去找到1T1R憶阻器記憶體的高阻抗跟低阻抗邊界電流。如此一來，使用者可以藉由邊界電流設置更好的參考電流。實驗結果顯示，如果使用我們提出的測試方法，我們可以減少10%的憶阻器被讀取錯誤。另一方面，高阻抗跟低阻抗的比值會隨者使用的時間越久而下降，為了解決這個問題，我們針對1T1R憶阻器記憶體提出一個線上監測和調校技術(OMT)。這種技術可以有效地延長記憶體的讀/寫週期。實驗結果顯示，OMT技術可以擴展憶阻器存儲器的壽命從10^5到10^6個存取周期。

Abstract
Memristor is a resistive device which is considered as an alternative non-volatile device for future non-volatile memories. For a memristor memory, a reference current is needed for discriminating the high-resistance (ROFF ) state from the low-resistance (RON) state. The reference current has an impact on the yield and reliability of the memristor memory. If we can identify the boundary currents of ROFF and RON, a good reference current can be set. Therefore, effective methods for identifying the boundary currents of memristor memories are needed.
In this thesis, we propose a test method in associate with a current comparing circuit for finding the boundary currents of ROFF and RON states of 1T1R memristor memories. Therefore, the user can set a good reference current according to the boundary currents. Simulation results show that if the test method is used to identify the boundary currents, 10% memristor cells which may be read incorrectly due to process variation for ROFF/RON
=3 can be eliminated. On the other hand, the ROFF/RON resistance ratio will decrease with the increasing of the read/write cycles in use. This results in the reliability issue. To cope with this issue, we propose a online monitoring and tuning(OMT) technique for the 1T1R memristor memories. The OMT technique can effectively prolong the read/write cycles of the memristor memories. Simulation results show that if the OMT technique can extend the lifetime of the memristor memory from 105 to 106 access cycles.

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