本研究以積體電路相匹配之Al、TaN作為上、下電極，以取代昂貴之白金(Pt)作為電極，並採用微波電漿氧化或反應式濺鍍製備中間電阻層TaOxNy，製成Al/TaOxNy/TaN、TaN/TaOxNy/Al之MIM結構之電阻式記憶體，比較兩種元件之電性掃描特性，且探討Al與TaOxNy界面處之界面氧化層AlOz對元件之影響。
當以微波電漿氧化或以反應式濺鍍製備中間層TaOxNy，並製作成Al/TaOxNy/TaN元件時，於循環掃描時高低電阻切換較不穩定，且不能長時間地作高低電阻切換，而高低電阻值會隨掃描時間增加而增加之趨勢，並直到元件產生永久絕緣現象而損壞。當以反應式濺鍍製備中間層TaOxNy，並製作成TaN/TaOxNy/Al元件時，元件於循環掃描時高低電阻切換穩定，且可循環操作高達1000次，而高低電阻值比值約2.5倍。
在TaN/TaOxNy/Al元件之導電機制方面，高電阻態之電性分析結果認為在低電壓時為Ohmic conduction，高電壓時為Poole-Frenkel emission；低電阻態則為Ohmic conduction。在電極面積效應方面，TaN/TaOxNy/Al元件之HRS電阻值會隨著面積增大而有下降之趨勢，LRS電阻值則維持不變，推測元件之導電方式是以導電燈絲作為主要導電機制。而於升溫電性量測分析，TaN/TaOxNy/Al元件之電阻值會隨著溫度上升而下降，可得知其導電燈絲為氧空缺燈絲作為主要載子傳遞路徑。

In this study, we demonstrate the effect of interfacial aluminum oxide (AlOz) layer near the Al-TaOxNy interface and compare reversible switching behaviors of the Al/TaOxNy/TaN and TaN/TaOxNy/Al resistance random access memory (RRAM) devices. The TaN and Al films which are compatible with the integrated circuits technology were prepared by sputter deposition as the electrode layers to replace expensive Pt electrode, and the tantalum oxynitride (TaOxNy) film was prepared by reactive sputtering or microwave plasma oxidation of the TaN films as the insulating layer.
The resistance swiching operation was unstable for the Al/TaOxNy/TaN devices whose TaOxNy films were prepared by reactive sputtering or microwave plasma oxidation, and the resistance of HRS and LRS increased with increased resistance switching cycles. In comparison, the switching behavior of TaN/TaOxNy/Al device whose TaOxNy film was prepared by reactive sputtering exhibited good stability. The resistance ratio of RHRS/RLRS measured at -0.2 V of the TaN/TaOxNy/Al device was about 2.5, and the numbers of resistance switching could be up to 1000 cycles at room temperature.
On the mechanism analysis of TaN/TaOxNy/Al device, HRS were the Ohmic conduction at the low operation voltages and the Poole-Frenkel emission at high operation voltages, respectively, and LRS was the Ohmic conduction. To elucidate the conduction mechanism, we carried out electrical measurements of the RRAM with different cell areas and at various temperatures. The TaN/TaOxNy/Al device in LRS had constant resistance with increased cell’s area and decreased resistance with increased temperature. It suggests that the electron transport is probably attributed to oxygen vacancies in conduction filaments.

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