本研究使用直流磁控濺鍍來沉積氧化銦錫（indium tin oxide, ITO），再用射頻磁控濺鍍與溶液凝膠法製成氧化鎳(nickel oxide, NiO)，將材料沉積於ITO基板上，形成ITO/NiO/ITO的金屬-絕緣層-金屬(metal-insulator-metal, MIM)結構之電阻式記憶體(resistive random access memory, ReRAM)，電阻式記憶體具有讀寫速度快、結構簡單、單元面積小、密度高、低電壓驅動、低耗電、高操作週期及非揮發性等優點，較傳統記憶體的表現還要優秀，故業界學界在電阻式記憶體上投入許多研究。而本研究以不同製程方式，製作出電阻式記憶體，並探討其電特性有何差異，再將電特性穩定之元件施加紫外光雷射照射，觀察電阻式記憶體對於光響應有何影響。紫外光和電阻式記憶體的整合中，可見光的高透射率和穩定可靠性的良好性能是持續的關鍵，而氧化鎳具有寬能隙、高遷移率、透明度、良好的電性及光學特質，在光學領域中有著廣闊的應用前景，如果未來將UV光結合到ReRAM元件製程中，這種特殊應用可以用在許多光電子顯示產品中。
本研究量測不同製程之ITO/NiO/ITO結構ReRAM的電特性做觀察，首先掃描電流電壓曲線，在耐用度測試上穩定達到100次循環，高低阻態在0.1V時磁控濺鍍製成之元件的電流比值最高達到三個階數(order)以上而溶液凝膠法製成之元件則不到一個階數，接著在記憶時間(retention time)可靠度方面的量測，經過104秒的量測後磁控濺鍍製成之元件大部分仍維持著資料完整性，而液凝膠法製成之元件則只有8 * 10^3秒後即失去資料記憶。最後將紫外光照射電阻式記憶體元件上，探討在不同尺寸下，紫外光照射對電阻式記憶體元件，對其高低阻態之電流有何影響。最後發現在最小的尺寸下，因導電燈絲生長比起較大尺寸來得不強健，使得在紫外光照射ReRAM後電阻值狀態發生改變，並提出模型加以說明。

Resistive switching memory is a system in which the resistance of a material can be modulated between two nonvolatile states by applying an electrical pulse, which has the combined advantages of fast read/write speed, simplicity in structure, small device size and density, low activation bias voltage, low power consumption, allowably many periodic operating cycles and nonvolatile memory feature. These devices are some of the most promising candidates for the next generation of non-volatile computer memories, while other plausible applications have also been sought such as bio-inspired neuromorphic systems. There have been a handful of studies on light controllable resistance switching, which concludes that optical illumination can improve switching properties or be an enabler for resistance switching. In these studies, the ultraviolet (UV) irradiation was used to control the resistance by modulating the current.
Among the materials considered, nickel oxide (NiO) potentially have a broad perspective in optical applications due to their relatively wide bandgap, high mobility, high transparency, remarkably good electrical and optical characteristics. Indium tin oxide (ITO) has well light transmittance and low resistance, which is suitable for illumination. In order to operate ReRAM in UV spectroscopic regime, the top and bottom electrode materials are made of ITO conductive film in order to facilitate the transmission of the UV irradiation. The spectral transparency of electrodes and reliable device performance are keys to ensuring its continual applicability. It is foreseeable in the future that unique applicability of ReRAM in UV will make its headway as a key component in many optoelectronic displaying products.
The present research focuses on using Radio Frequency Magnetron Sputtering and sol-gel processing method to prepare NiO active layers. Then, the DC Magnetron Sputtering method is also adopted to deposit indium tin oxide (ITO) top electrode for the realization of the semi-transparent ReRAM devices and their current-voltage characteristics are subsequently evaluated.
Specifically, a series of reliability tests have shown that the fabricated memories have endured up to 100 switching cycles. Here, the samples of the largest dimensions prepared by the Magnetron Sputtering method show that the current contrast ratio between high (HRS) and low (LRS) resistance state at 0.1V has achieved more than three orders of magnitude. Furthermore, the retention time measurement has also demonstrated that the memory storage capability of these ReRAMs remain in excellent operating condition after surviving more than 10,000 seconds of the test while the smallest size devices have yielded a substantially less data retention capability. In comparison, the typical memory state of the ReRAM fabricated by sol-gel processing method could not sustain more than 8,000 seconds.
Finally, the extent of UV irradiation impact on ReRAM is then investigated. Major attention are concentrated in finding out a correlation between the UV responsivity and switching characteristics for NiO ReRAMs under study at low bias voltage. We found that the memory states associated with the ReRAM of the smallest feature sizes could be toggled relatively easy by UV irradiation at the smallest size.

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