本研究以Ti及ITO作為電阻式記憶體之電極，並藉由Ti金屬之高氧化勢而自身氧化成TiOx電阻層，因此可在無需額外濺鍍電阻層下製成Ti/ITO與ITO/Ti之電阻式記憶體。
TiN/Ti/TiOx/ITO元件為雙極式電阻式記憶體，且無需以高電壓forming；其掃描方向為逆時針方向，分別在正向偏壓1.16 V處切換(Set)為低電阻態，在負向偏壓-1.00 V處切換回(Reset)高電阻態；且元件來回穩定掃描可達500次，其高低電阻比值可達8倍。其中，在TiN/Ti/TiOx/ITO元件導電機制部分可發現，當元件掃描至穩定後，其低電阻態之導電機制為Ohmic conduction，高電阻態在低電壓符合Ohmic law而高電壓則為Poole-Frenkle emission。接著，利用電極面積之影響可發現，TiN/Ti/TiOx/ITO元件在高電阻態時，其電阻值隨面積增大而變小，而低電阻態不隨電極面積改變，由此可推測元件藉由燈絲路徑作為導電方式；另外，在溫度效應方面則可以發現在高低電阻態時，其電阻值皆會隨溫度上升而下降，因此可推測TiN/Ti/TiOx/ITO元件導電方式以氧空缺作為導電燈絲路徑。
最後，本實驗另製作ITO/TiOx/Ti/TiN元件，此元件也屬於雙極式電阻式記憶體，而掃描方向則為順時針方向，分別在正向偏壓2.0 V處切換(Reset)為高電阻態，在負向偏壓-1.4 V處切換回(Set)低電阻態。且發現ITO/TiOx/Ti/TiN元件在多次掃描後高低電阻比值僅達1.5倍且較為不穩定。而導電機制在低電阻態時為Ohmic conduction，高電阻態為空間電荷限制傳導(Space-charge-limited conduction)。因此為改善元掃描之穩定性及高低電阻比值，本實驗將ITO/TiOx/Ti/TiN元件在250℃下進行真空退火30分鐘，確實有效改善元件切換之穩定性。

In this study, we used titanium (Ti) and indium tin oxide (ITO) as the eletrodes to fabricate the TiN/Ti/TiOx/ITO and ITO/TiOx/Ti/TiN resistance random acess memory (RRAM) without depositing a resistor layer. It was found that an interfacial-oxide layer TiOx was spontaneously formed between Ti and ITO layers.
The TiN/Ti/TiOx/ITO device showed bipolar switching of resistance in counterclockwise direction without forming a process. The TiN/Ti/TiOx/ITO device changed from high resistive state (HRS) to low resistive state (LRS) at about 1.16 V and changed back to HRS at about -1.00 V. The endurance test showed resistance ratio, RHRS/RLRS, for TiN/Ti/TiOx/ITO device was 8, and the DC voltage sweeps could achieve about 500 cycles at room temperature. The conducting mechanism for TiN/Ti/TiOx/ITO device followed Ohmic cconduction at LRS. And the HRS also followed Ohmic cconduction at low voltage, but Poole-Frenkel emission at high voltage. Furthermore, the area-dependence characteristic of resistance for the TiN/Ti/TiOx/ITO device was constant at LRS, but decreased with increased areas at HRS. And the characteristic of resistance was increased with temperatures for the TiN/Ti/TiOx/ITO device at LRS and HRS. Filamentary path of oxygen vacancies was suggested to dominate the conduction in the TiN/Ti/TiOx/ITO device.
The ITO/TiOx/Ti/TiN device also showed bipolar switching of resistance but in clockwise direction without a forming process. And the ITO/TiOx/Ti/TiN device could be reset from LRS to HRS at about 2.0 V and set back to LRS at about -1.4 V. Furthermore, the resistance ratio, RHRS/RLRS, was around 1.5 and unstable for the ITO/TiOx/Ti/TiN device. After switching stably, the conducting mechanism of ITO/TiOx/Ti/TiN device followed Ohmic cconduction at LRS, but combined Ohmic at low voltages and space-charge-limited conduction at high voltages at HRS. By annealing it in vacuum at 250 ℃ for 30 min, the ITO/TiOx/Ti/TiN device had stable switching behavior.

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