將生物可分解的天然性材料應用於電阻式記憶體的絕緣層之中具有製程容易、低成本、環境友善以及生物相容的特性。本論文中，利用柑橘果膠製作電阻式記憶體元件。以旋轉塗佈的方式形成柑橘果膠薄膜在氧化銦錫基板上，並攝氏50度下烤乾30分鐘，最終以蒸鍍的方式沉積鋁作為上電極。其元件結構為Al/柑橘果膠薄膜/氧化銦錫/玻璃。本研究中，首先調整柑橘果膠水溶液的濃度，以及旋轉塗佈的轉速，來獲得特性表現最佳的柑橘果膠電阻式記憶體。以濃度為2mg/ml轉速1000rpm40s的元件特性最好，開關電流比值約為5×〖10〗^2，循環切換次數達到181次，寫入、抹除電壓分別為-0.58 V和2V，而且資料保存時間超過〖10〗^4秒。
因柑橘果膠電阻式記憶體的開關電流比仍有提升的空間，故將銀摻雜到柑橘果膠之中，讓元件中產生兩種燈絲，以提升元件的操作特性。以銀摻雜濃度10%的元件特性表現最佳，開關電流比值約為2×〖10〗^3，循環切換此數高達517次，展現優秀的元件穩定度及耐受度，寫入、抹除電壓分別為1 V和-1.2V，而且資料保存時間超過〖10〗^4秒。
最後針對柑橘果膠電阻式記憶體以及銀摻雜柑橘果膠電阻式記憶體多層儲存的特性做研究，發現藉由調整不同的限制電流，可以在單一元件中形成四種不同的電阻態，且四種狀態都具有良好的穩定度以及可靠度，也證實可以在單一個元件中儲存2個bit。本研究之元件相較於其他生物性材料記憶體元件有較優秀的元件耐受度及可靠度。

Resistive switching memory based on natural material has the advantages of simple procedure, low cost, environmental friendly and biocompatible. In this thesis, citrus pectin is applied on resistive switching memory. A thin film of citrus pectin is formed on an ITO substrate by spin coating method, and then baked at 50°C for 30 minutes. Finally aluminum is deposited as the top electrode by thermal evaporation. The device structure is Al/citrus pectin thin film/ITO/glass. The first part in this research is adjusting the concentrations of citrus pectin solution and the spin rates of spin coating method to obtain the best performance of citrus pectin resistive switching memory. The device with concentration of 2 mg/ ml and the spin rate 1000 rpm for 40 s shows the best performance. It can switch 181 times with on/off ratio5×〖10〗^2 and maintained up to 〖10〗^4s. Set and reset voltage of the device are -0.58V and 2V, respectively.
Since there is still room to improve the on/off ratio of the citrus pectin resistive memory, silver is doped into the citrus pectin. There are two types of filaments in the device which improve the performance of the device. The device with silver doped 10% has the best performance. It can switch 517 times with on/off ratio2×〖10〗^3 and maintained up over 〖10〗^4s which indicated excellent stability and reliability. Set and reset voltage of the device are 1V and -1.2V, respectively.
Finally, the characteristics of multilevel storages of citrus pectin resistive memory and silver-doped citrus pectin resistive memory were investigated. By adjusting different compliance currents, four different resistive states could be formed in a single device with good stability and reliability. In other words, these devices could store two bits in a single cell. Compared with other biomaterial based resistive random access memory devices. The devices in this work have more switching cycles and long retention time.

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