將鐵磁金屬自旋注入半導體研究中，最大的困難來自於在它們之間的能帶不匹配。為了能在正確地量化自旋注入，自旋發光二極體是透過量測左旋和右旋光去分析自旋極化率，因此自旋發光二極體是一個相當有助益的工具。
在這研究裡，我們已經研究了由鐵三矽和砷化鎵異質結構所構成的自旋發光二極體，鐵三矽可視為Heuslar alloy，因此被期望在費米能階上自旋極化率為100%，故使得鐵三矽成為自旋注入上最有吸引力的材料。這些薄膜的成長皆在超高真空整合式多腔體系統裡所完成，在完成三五族半導體成長後，試片在未破真空下傳輸至另一個腔體並且成長150Å鐵三矽，鐵三矽與砷化鎵(100)只有-0.2%晶格不匹配.
在透過有系統地製程改善與結構設計後，並利用光學機台量測後證實光強度已大幅增加1000倍。
此外穿隧能障已經被知道可以解決在鐵磁金屬與半導體能帶不匹配的問題，進而改善自旋注入的效率。在這研究裡，我利用參雜的改變在鐵三矽與半導體界面上形成Schottky能障，並且有許多材料也可型成穿隧能障，我們計畫未來利用單晶的氧化鎂去研究鐵三矽/氧化鎂/砷化鎵穿隧界面。

The difficulty of spin injection from a ferromagnetic metal into a semiconductor originates from the conductivity mismatch between these materials. The spin-polarized light-emitting diode (spin-LED) is a very powerful means for accurately quantifying spin injection through detecting left and right circular polarized light.
In this work, we have investigated the spin-LEDs made of Fe3Si/GaAs heterostructures. Fe3Si, as a Heusler alloy, is expected to be half metal with 100% spin polarization at the Fermi level, thus making Fe3Si an attractive material for spin injection. The film growth was conducted in a UHV, multi-chamber integrated system. After III-V growth, the sample was transferred in-situ to another chamber for depositing 150 Å thick Fe3Si film epitaxially grown on GaAs(100) surface with -0.2% lattice mismatch.
Our optical measurements have demonstrated the successful enhancement of the LED brightness by 1000 times through systematic improvements of the fabrication process and design of the LED structure.
Furthermore, a tunnel barrier is known to remove the problem of the conductivity mismatch between a ferromagnetic metal and a semiconductor, thus increasing the spin polarization efficiency. In the research, I use doping engineering to form a Schottky barrier at Fe3Si and semiconductor. And Among many materials candidates as tunnel barriers, we plan to employ crystalline MgO oxide films to investigate the spin injection of Fe3Si/MgO/GaAs tunnel junction in the future.

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