人類的科技發展離不開資料儲存，過往使用的隨機存取記憶體如DRAM、SRAM皆為揮發性記憶體，因為此特性這些記憶體的運作需要不間斷的提供電源，在車載電腦、行動裝置、物聯網等科技蓬勃發展下，這樣的特性成為最大的缺點。
磁性記憶體具有高讀寫速度與非揮發性的特點，因此被視為下一世代記憶體的翹楚。本篇論文基於自旋軌道矩磁性記憶體的基礎，透過含有非磁性重金屬的反鐵磁作為自旋電流來源進行一系列的研究。過去水平磁矩是否翻轉的量測需要將元件做成磁穿隧接面或使用磁光柯爾效應，但兩者都將使量測時間與製造成本上升，本論文提出利用異向性磁阻量測水平磁矩的翻轉，此方法快速且所需儀器成本顯著降低，替後續水平磁矩翻轉量測提供另一種量測方式。同時在反鐵磁相的白金錳/鐵磁系統中，我們發現了一種異常的自旋軌道矩翻轉行為，當反鐵磁態白金錳成相後我們可以使用正負電流翻轉磁矩，相比於過去的結果，這是一個十分特別的翻轉行為，為此我們設計一系列實驗來研究此現象的起因與可能性。

Data storage is the foundation of the revolution of human technology. Most of the previous random access memory we used are volatile, such as DRAM, and SRAM. They are called volatile memory because electricity is needed while working. This characteristic becomes the most significant disadvantage as car computers, mobile devices, and IoT attracts more and more attention.
Magnetic random access memory is a good candidate because of its high speed and non-volatile feature. This thesis is based on spin-orbit torque MRAM. We used heavy metal-based antiferromagnetic PtMn as a spin current source to start our research. It was hard to measure in-plane magnetic moment previously. Magnetic tunneling junctions or magneto Kerr effect are needed. However, these two methods take enormous time and cost a lot. We proposed a new method based on anisotropic magnetoresistance to measure in-plane magnetic moment switching. AMR measurements are much easier and cheaper than those used before. An anomalous spin-orbit torque switching behavior was discovered at the same time. As long as our PtMn phase transformed into an antiferromagnetic phase, we could switch the magnetization by both positive and negative currents, which are quite different from others’ results. We designed a series of experiments to dig out the possible reason.

摘要 2
Abstract 3
致謝 4
第一章 緒論 10
1.1研究起源 10
1.2 大綱 10
第二章 文獻回顧 11
2.1 磁性記憶體的發展 11
2.1.1 磁性記憶體的運作 11
2.1.2 磁場寫入 11
2.1.3 自旋轉移矩 (Spin Transfer Torque, STT) 11
2.1.4 自旋霍爾效應 (Spin Hall Effect, SHE) 12
2.1.5 拉什巴效應 (Rashba Effect) 14
2.1.6 自旋軌道矩 (Spin Orbit Torque, SOT) 14
2.2 白金錳反鐵磁性質 17
2.2.1 自旋結構 (Spin Texture) 17
2.2.2 相變化 18
2.2.3 交換偏壓 (Exchange Bias) 19
2.3 異向性磁阻(Anisotropic Magnetoresistance) 20
2.4 單極與雙極翻轉 21
2.5 磁光柯爾效應(Magneto-optic Kerr effect, MOKE) 23
第三章 儀器介紹 24
3.1 高真空磁控濺鍍儀 24
3.2 高真空退火系統 25
3.3 震盪樣品磁量測儀 26
3.4 原子力顯微鏡 27
3.5 X-ray繞射機 28
3.6 黃光微影 29
3.7 乾式蝕刻機 30
3.8 四點探針 31
3.9 磁光柯爾顯微鏡 32
第四章 實驗設計與樣品量測與討論 33
4.1 實驗設計 33
4.2 樣品性質 33
4.3 樣品量測 35
4.3.1 異向性磁阻量測 35
4.3.2 磁光柯爾效應量測 36
4.4 介面自旋排列 36
4.5 異常自旋軌道矩磁矩翻轉 37
4.6 改變鐵磁層材料 39
4.7 改變反鐵磁層成分比例 41
4.8 改變反鐵磁層厚度 46
4.9 插入鈀改變介面性質 47
4.10 使用Type-X翻轉 51
4.11 鉭產生自旋電流協助翻轉 53
4.12 改變反鐵磁種類 55
4.13 交換偏壓效應 56
第五章 結論與未來工作 57
第六章 參考文獻 59

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