在這項研究中，使用溶膠凝膠法在 ITO/玻璃基板上製備非晶 Ce2Ti2O7(CTO)薄膜。研究薄膜厚度、上電極、退火溫度、金屬後退火以 及在 CTO 薄膜和 ITO/玻璃之間插入額外的 AlOx 層對元件電阻切換特性 (RS)的影響。所有樣品均表現出雙極電阻開關(BRS)行為。在金屬後退火 (PMA)處理下的樣品中觀察到 Al 和 AlOx 在 Al/CTO 界面處的擴散與形 成。擴散的 Al 原子可以作為摻雜劑提供額外的氧空位，而自形成的 AlOx 則有助於阻止氧離子向外擴散。經過金屬後退火的 Al/CTO/ITO 樣品展示 1565次的開關週期，–1.1 V/1.0 V之低工作電壓，電阻比(Ron/Roff)約為100， 保留時間(Retention time)在常溫下可達 一萬秒。另外，在 CTO/ITO 界面插入 AlOx 層的元件(Al/CTO/AlOx/ITO)，其開關週期提高到1926次，電阻比提升至1000，使其成為 RRAM 應用中具有前途的候選者。本研究的電流傳導機制在低阻態(LRS)的 Set 和 Reset 過程中，均表現出斜率為~1 的線性關係，為歐姆導通。在 HRS 中表現出~2 的斜率，為陷阱控制的空間電荷限制傳導 (SCLC)。

In this study, amorphous Ce2Ti2O7 (CTO) thin films were prepared on ITO/glass substrates using the sol-gel method. The effects of film thickness, annealing temperature, post-metal annealing, and the insertion of an additional AlOx layer between the CTO thin film and ITO/glass on the resistive switching (RS) characteristics of the devices were investigated. All samples exhibited bipolar resistive switching (BRS) behavior. During the post-metal annealing (PMA) treatment, diffusion and formation of Al and AlOx at the Al/CTO interface were observed. The diffused Al atoms acted as dopants, providing additional oxygen vacancies, while the self-formed AlOx layer contributed to preventing the outward diffusion of oxygen ions. The Al/CTO/ITO samples subjected to metal annealing demonstrated 1565 switching cycles, low operating voltages of –1.1 V/1.0 V, a high resistance ratio (Ron/Roff) of ~100, and retention time of 10000 s at room temperature. Furthermore, devices with an AlOx layer inserted at the CTO/ITO interface (Al/CTO/AlOx/ITO) showed improved switching cycles and resistance ratio, making them promising candidates for resistive random-access memory (RRAM) applications. The current conduction mechanism in the low-resistance state (LRS) during the Set and Reset processes exhibited a linear relationship with a slope of ~1, indicating Ohmic conduction. In the high-resistance state (HRS), a slope of ~2 was observed, indicating trap-controlled space charge-limited conduction (SCLC).

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