本論文是研究單層之硫氰酸亞銅(CuSCN)材料作為電阻式記憶體(RRAM)元件之電性探討。我們在成長CuSCN這層薄膜的方法為電化學沉積。上電極的選擇是採用惰性金屬，白金(Pt)，以防止電極因施加電壓成離子而擴散至下層材料，導致元件特性受到影響。
不同濃度成長的CuSCN薄膜會呈現出不同的表面形態，在經由電性的量測後，並由兩個阻態的電阻穩定性來選擇最後CuSCN薄膜之製作濃度，我們選擇12 mM成長的CuSCN作為元件之薄膜且厚度最佳化的值為800 nm，X光繞射儀(XRD)及掃瞄式電子顯微鏡(SEM)顯示出CuSCN之晶粒沿(003)之面向呈柱狀生長，這對元件之耐久性(Endurance)，穩定性及電壓分布範圍皆很有影響。
在電性上，Forming process時，電流的限流設定為2 mA，而forming 電壓大約在8.3 V左右。在電阻絲機制分析上，低阻態(LRS)漏電流的形式是歐姆傳導(Ohmic Conduction)，高阻態(HRS)的漏電流在小偏壓下是以歐姆傳導，而隨著偏壓變大後機制轉變為有限的空間電荷電流機制(Space Charge Limited Current)為主導。電阻值方面，兩阻態在元件重複循環操作100次正偏壓及負偏壓做Endurance之量測，高阻值及低阻值的比例範圍在25倍至50倍，兩阻態的阻值都很穩定。於100 mV下讀取高阻態及低阻態持續10000秒做操作週期(Retention)之量測，兩阻態阻值比至少都有10倍以上。在電阻分布圖中顯示出兩阻態之範圍，低阻值大約為100 Ω到400 Ω，而高阻值大約為4000 Ω到8000 Ω，而在電壓分布圖上，兩種阻態的電壓分布範圍也很小，set電壓大約在0.4 V ~ 0.9 V而reset電壓大約在-0.2 V ~ -0.9 V，以上資料可看出此CuSCN作為RRAM元件的優點為: 操作之功率消耗小且兩個阻態在操作上穩定。

This study investigates the characterizations of electrodeposited CuSCN film as a RRAM device. The device structure is Pt/CuSCN/ITO glass. To prevent the metal ion diffusion of the top electrode, which can affect device characteristics when we apply the voltage, inert metal Pt was used.
Preliminarily device characterizations were performed using various concentrations to form the CuSCN film, the 800 nm thick 12 mM-formed CuSCN was selected due to its stable resistances in both high and low resistance states. SEM and XRD analyses show that the CuSCN film has a strong (003) peak and is c-axis oriented with columnar grains growth.
The current compliance is set to 2 mA to test the forming process, the data show that the forming voltage is ~8.3 V. As for the current mechanism of the device, the low resistance state (LRS) follows the ohmic conduction. For the high resistance state (HRS), it follows the ohmic conduction also in low voltages, however, the space charge limited current (SCLC) mechanism dominates the current conduction when the applied voltage gets higher. The endurance and retention of the CuSCN RRAM was evaluated, we did the WRER(Write-Read-Erase-Read) test for measuring the resistance of the device for 100 cycles and read at 100 mV. For device endurance, it shows that the ratio of R_HRS to R_LRS (R_HRS/R_LRS ) is ranging from 25 to 50 times, and the resistance of two states are stable. In retention test, we read at 100 mV in two resistance states for a duration of 10000 seconds, it shows that the ratio of R_HRS to R_LRS is at least 10 times. Under 100 mV cumulative plot of the resistance, it shows that the resistance of the high resistance state and the low resistance state are ranging from 100 Ω to 400 Ω and from 4000 Ω to 8000 Ω, respectively. The set voltage V_set is 0.4 V ~ 0.9 V and reset voltage V_reset is -0.2 V ~ -0.9 V, from the distributions of set and reset voltages, power consumption of the CuSCN RRAM is very low, and the voltage ranges of the V_set and V_reset are small.

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