在要求元件的速度和輕薄化的同時，傳統的Flash記憶體已經不能滿足其要求，因此各種不同新世代的記憶體結構紛紛被提出，其中電阻轉換式記憶體(RRAM)，因為具有體積小，結構簡單，速度快等特點，被各界視作新一代記憶體的有利候選，因此我們使用RRAM作為研究的主軸。MIM RRAM 除結構簡單的優勢之外，還具有低壓操作等種種優點，極具發展潛力，而MIS RRAM元件具有除具有RRAM元件一貫優勢之外，因為使用的是半導體基板，在加上製作流程簡易，容易整合於與現有的工業製程中，製程簡易，在使用上具相當的彈性。我們從Dongsoo Lee.,et al[1]在2005年發表的文章得到靈感，使用Zr-base氧化物作為為元件介電薄膜，並參考Szot,K.,et al[2]的文章：藉由在介電中參入Ti (SrTiO3)，使元件表現出較好的電性。
綜合以上兩種想法，我們選用ZrTiOx(ZTO)為介電材料，製作MIS及MIM結構RRAM，我們選用電子槍蒸鍍系統，在半導體基板(矽，鍺)或是金屬下電極上，蒸鍍ZTO (ZrTiOx)介電薄膜及金屬上電極，製作結構MIS(Metal/Insulator/Semiconductor)及結構MIM(Metal/Insulator/Metal)的電阻轉換式記憶體，並更改基板，電極的材料，及介電薄膜ZTO的厚度和其他製程流程，改善元件的電性。
由實驗結果發現，依據結構(基板、電極材料種類)不同，元件都展現出不同的電阻轉換特性，由實驗的結果，可發現元件的電性受電極及基板材料的配合極大，相信是受材料特性的不同所影響。之後我們針對介電薄膜作各式的後段處理，以不同溫度的高速退火使介電薄膜結晶，並研究其對元件的影響。其中結構為Pt/Ti/ZTO/n+ Ge 及 Pt/Ti/ZTO/Pt元件在各方面表現尤其出色，相信具有足夠的發展潛力。
由於RRAM的電阻轉換的確切機制並不明朗，因此我們更加重視機制的探討，利用實驗結果及物性分析，並考慮其材料特性和漏電機制，比對各種電阻轉換現象的理論，對我們元件的電阻轉換現象提出相符的電阻轉換機制解釋。自漏電機制的機制判別，我們認為實驗元件的電阻轉換機制屬於氧空缺(Oxygen Vacancy)造成的filament theory。

Resistive random access memory (RRAM) is one of the most promising new generation memory device candidates. In our research, we applied ZrTiOx (ZTO) thin film in metal/insulator/semiconductor (MIS) and metal/insulator/metal (MIM) structured RRAM. cells with a thin oxygen-deficient ZrTiOx film and try to make devices show good properties.
As our experiment results, we found that ZrTiOx based RRAM devices show different properties with different device structures and production process. For example, devices with structure Ni/ZTO/n+ Ge demonstrate a unipolar switching behavior and with structure Pt/Ti/ZTO/n+ Si demonstrate a bipolar switching behavior. MIS RRAM devices with Pt/Ti/ZTO/n+ Ge structure demonstrate a stable bipolar switching behavior, and show small operation voltage (SET V:2.4V, RESET V:-2.05 V), fast operation speed (500 ns), good R/S ratio(104), Endurance(104 times), and data retention(105 sec, @85oC). MIM RRAM with Pt/Ti/ZTO/Pt structure also show small operation voltage (SET V:0.47V, RESET V:-0.73 V), fast operation speed (100 ns), good R/S ratio(86x), Endurance(104 times), and data retention(105 sec, @RT). Both devices show promising properties as nonvolatile memory devices. To understand the resistance switching phenomenon of devices, we observe the I-V curves of devices, and believe that the switching phenomenon induced by filament theory.

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