本研究以具有銦錫氧化物(Indium tin oxide，ITO)薄膜的玻璃為基材，反應濺鍍氧化矽中間電阻層，濺鍍摻鋁氧化鋅(Aluminum-doped zinc oxide，AZO)為上電極，製作出AZO/SiOx/ITO三層結構之透明電阻式記憶體。
AZO/SiOx/ITO元件展現出正向偏壓下Set，負向偏壓Reset的穩定雙極式切換性質，能操作電阻切換至少達到100次以上，且高低電阻比值可達將近16，為良好的電阻式記憶體元件。
進一步分析電阻切換機制，配合XPS分析結果得知中間電阻層氧化矽中含有鋅元素，以及低電阻態電阻隨溫度上升而上升，屬於金屬導電性質，因此我們推測AZO/SiOx/ITO元件電阻切換為金屬鋅燈絲形成與中斷所致。低電阻態分析結果於低電壓時屬於歐姆接觸，高電壓時符合普爾-法蘭克發射機制；高電阻態分析也是低電壓時為歐姆接觸，高電壓下符合普爾-法蘭克發射機制。
分析不同處理後AZO/SiOx/ITO元件的性質變化，經過退火處理的元件其Forming電壓下降，可推測為鋅擴散分布更廣，使得元件易形成導電路徑之故；中間電阻層氧化矽經微波氫氣電漿還原處理後，除了Forming電壓明顯下降外，其高電阻態機制分析屬於空間電荷限制傳導，可以推測歸因於還原處理，使得中間電阻層中氧減少及缺陷產生造成，另外缺氧的氧化矽搶氧化鋅的氧，使得中間電阻層中金屬鋅含量增加，造成元件電阻值下降。
最後對AZO/SiOx/ITO元件進行穿透率測試，元件於可見光範圍穿透率可達到85 %以上，甚至於440 nm波長可達到95 %以上的穿透率，說明此元件具有高度透光性，為透明電阻式記憶體。

For constructing the transparentresistance random access memory(RRAM), we use indium tin oxide(ITO) as the bottom electrode, silicon oxide (SiOx) as the insulator, and aluminum-doped zinc oxide (AZO) as the top electrode to fabricate AZO/SiOx/ITO transparent RRAM.
The as-prepared transparent RRAM is in high resistance state (HRS). The RRAM required a forming process by applying a positive bias on the top electrode to switch to low resistance state (LRS). Then transparent RRAM exhibited bipolar switching of resistance. This RRAM performed two resistance state with resistance ratios, RHRS/RLRS, of about 16 during 100 cycles of endurance testing.
In X-ray photoelectron spectroscopy analysis, zinc was present in silicon oxide. Further study of temperature dependence of resistance showed that resistance in LRS rises with temperature increasing. Therefore, we suggested that the resistance switching was due to the forming and rupturing of zinc filament in the SiOx. Electrical characterization resulted in low resistance state showing ohmic conduction in low voltage, with Poole-Frenkel emission in high voltage. The high resistance state also showed ohmic conduction in low voltage, and Poole-Frenkel emission in high voltage.
Whether the devices were treated by annealing or reduction, they all presented lower forming voltage and lower resistance than the as-prepared one. We suggest that it was caused by diffusion of zinc or reducing ZnO to zinc in silicon oxide layer. After reduction treatment, the devices showed space-charge-limited-conduction in high resistance state. It could be speculated that due to producing more defect during reduction. In addition, silicon is more easy to oxidation than zinc. So there were more zinc content in silicon oxide layer to reduce the resistance.
This AZO/SiOx/ITO device showed highly transparent in visible region. The average transmittance is over 85%, even in 440 nm wavelength, it showed more than 95%. This RRAM has potential to be integrated in transparent electronics in the future.

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