相變化記憶體(phase change memory)是近年來備受矚目的非揮發性記憶體。其係利用電流脈衝使薄膜升降溫，使記憶體在非晶態 (高阻態)與結晶態 (低阻態)之間進行快速且可逆地相變化，以達到儲存資料之目的。Ge2Sb2Te5為一最常用於相變化記錄之相變材料，由材料的觀點視之，仍有許多缺點需要改進：Ge2Sb2Te5之結晶溫度低(~160 ℃)使得非晶態之溫度穩定性不足，造成記憶體之數據留存溫度不足；且其熔點高(~ 620 ℃)造成記憶體非晶化的過程中需要過高的RESET電流脈衝，造成過多之能量耗損。
本研究第一部份探討硼離子佈植於Ge2Sb2Te5，藉由硼離子引入進行材料改質。當硼含量增加(佈植劑量5E14至5E15 ion/cm2)，結晶溫度分別達167 ℃和169 ℃，提高2和4℃。再藉由恆溫結晶動力學可計算出結晶活化能分別為2.92與2.96 eV，並利用外插的方式估計其十年的數據留存溫度分別比未佈植者提高2和5℃，達85 ℃和88 ℃。晶體結構分析顯示，當劑量達到5E15 ion/cm2時，硼離子可部分抑制高溫HCP相的形成。結晶化所需時間隨著劑量增加而上升。
第二部份探討矽離子佈植於Ge2Sb2Te5，藉由矽離子引入進行材料改質。當矽含量越高(佈植劑量5E15至5E16 ion/cm2)，結晶溫度達177 ℃和178 ℃，有效提高12和13℃。。由恆溫結晶動力學可計算出結晶活化能分別為3.3與3.9 eV，並利用外插的方式估計其十年數據留存溫度分別比未佈植者提高13和24 ℃，達96 ℃和107 ℃，如此可有效提升Ge2Sb2Te5非晶態穩定性。晶體結構分析顯示，隨著佈植劑量上升，可有效阻礙晶粒成長。因此結晶態電阻上升，可以降低操作電流與減少能量耗損。當劑量達到5E16 ion/cm2時，矽離子已完全抑制HCP相形成。結晶化所需時間隨著劑量增加而上升。

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