由於一次性電子產品發展快速，造成大量的電子廢棄物產生。雖然無機材料應用於半導體元件中的技術已經相當成熟，且無機材料具有良好的器件性能，但仍無法忽視背後對整個生態系統所造成的負面影響。反觀可再生有機材料，有著成本低、製作簡單、機械性能優良、可在低溫溶液中使用等等的優點，提供電子元件材料另一種選擇。本研究中我們以金屬絕緣體金屬（Metal-Insulator-Metal, MIM) 的架構進行元件設計，並以可再生材的生物性材料柑橘果膠(citrus）作為絕緣層，分別製作成電阻式隨機存儲記憶體(Resistance Random Access Memory, RRAM)以及有機光感測器 (Organic Photodetector, OPD)。
在RRAM的研究成果中我們發現，柑橘記憶裝置具有穩定的電阻轉換行為。為了清楚地了解上電極金屬和柑橘薄膜間的界面影響，我們研究了不同上電極 (TE) 材料對元件電阻轉換的影響。與Au/citrus/ITO 和 Ti/citrus/ITO 元件相比，Al/citrus/ITO 元件可以在直流電壓下進行100個I-V cycles，而 阻值比僅略有下降。此外， Al/citrus/ITO 元件具有超過 104 的高 ON/OFF 比和出色的均勻性，這歸因於使用上電極Al可與柑橘間的界面快速形成氧化物層 (AlOx)，提升並穩定元件的性能。 除了RRAM的應用，我們也試圖將柑橘果膠作為OPD的主動層進行測試，研究中我們將柑橘果膠並摻入硝酸鋁 (AlC05) 的OPD。透過電性量測，發現 0.5 mg/mL 的 AlC 濃度可提供最高的開/關比和可接受的上升和下降時間。此外優化後的元件（Al/AlC05/ITO）在 440 nm 可見光下在 0.1 V 偏壓下表現出良好的穩定性和可重複性。
從研究成果得知，我們利用可再生材料並以溶液法製備的生物性元件，具有各項可靠及穩定的表現。這些發現及應用可作為未來電子元件永續發展發展的設計指南。

The generation of electronic waste is rapidly increasing despite of the development in the disposable electronic products. The semiconductor technology based on inorganic materials is quite mature due to its reliable device performance, however, the negative impact of electronic wastes on the entire ecosystem cannot be ignored. In contrast, renewable organic materials-based semiconductor technology has the advantages of low-cost manufacturing, simple production, excellent mechanical properties, and can be fabricated in low temperature solutions, providing alternative option for electronic component materials. In this study, we utilized the Metal-Insulator-Metal (MIM) structure to fabricate resistive random-access memory (RRAM) by using the renewable biomaterial citrus pectin (citrus) as the insulating layer that can also employed as an organic Photodetector (OPD).
In the detailed study, the citrus memory device has been found with stable resistance switching performances. It was very crucial to understand the interfacial effect between the top electrode metal and the citrus film, so we investigated the effect of different top electrode (TE) materials on the resistive switching of the element. Al/citrus/ITO devices exhibited 100 I-V cycles at DC voltage with a very slight drop in resistance ratio compared to Au/citrus/ITO and Ti/citrus/ITO devices. In addition, the Al/citrus/ITO element possessed a high ON/OFF ratio of more than 104 with excellent uniformity, which can be attributed to the rapid formation of oxide layer (AlOx) at the interface between Al and citrus insulating layer and stabilized the device performance.
In addition, we also tried to optimize the active layer of OPD by incorporating citrus pectin with aluminum nitrate (AlC0.5). The effects of different concentrations of aluminum nitrate on the morphology and optical properties were further investigated using SEM, UV-vis and AFM. The electrical measurements satisfied the AlC concentration of 0.5 mg/mL provided the highest ON/OFF ratio and acceptable rise and fall times. Nevertheless, the optimized device (Al/AlC0.5/ITO) structure exhibited good stability and repeatability below 0.1 V bias under the visible light of 440 nm wavelength.
Based on the results, the bio-electrical devices prepared by the solution method using renewable materials have various reliable and stable performances. These devices can serve as design guidelines for the sustainable development of future electronic technology.

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