近年來，人類對於電子產品的需求越來越高，而記憶體成為科技中不可或缺的重要部分，為了追求更卓越的性能，記憶體不斷朝著輕薄短小的高密度尺寸、高速度、低耗能等目標前進。
FLASH 是利用浮動閘 (floating gate)來儲存載子單元，然而其中的穿遂氧化層 (tunneling oxide)卻會影響FLASH的特性，如當FLASH微縮時，可能導致穿遂氧化層 (tunneling oxide)太薄而漏電，使得記憶體記憶能力變差，且讀取方式為破壞性讀取，傷其元件，其他如耐久力和操作速度慢都是FLASH的缺點。
然而電阻式記憶體 (RRAM)製成簡單，且擁有高速率、低耗能、結構簡單化、高操作週期、並且擁有非破壞讀取及非揮發性等多項優勢，所以除了在特性上的突破與改進，在生產成本上亦有相當大的優勢，因此受到學術界及業界等眾多矚目，是目前唯一能與具備低成本競爭力的 NAND 型快閃記憶體對抗的記憶體。
並有機會成為下個世代記憶體的領航者。
本論文主要分為兩部分去探討二氧化鉿 (Hf O2 )在雙極電阻轉換上的現象。
第一部分以濺鍍方式鍍製不同氧通量Hf O2薄膜，並以TiN當下電極，Pt 當上電極形成 Pt/TiO 2 /TiN 的結構。討論元件其電性的改變。
第二部分是以原子層化學氣相沉積系統 (ALD)成長的HfOx薄膜，並在HfOx薄膜上面分別沉積Ti CAP與Zr CAP，再沉積1500Å TaN，並以Pt做為下電極，形
成TaN/ Ti (或Zr) / HfOx / Pt結構的RRAM，進而討論其電特性有何不一樣。

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