奈米磁鐵FePt在PN接面二極體結構之磁電耦合特性

Abstract

二極體元件，在積體電路中一直具有相當廣泛的應用，其元件物裡和特性更是半導體元件的基石，而在現今半導體元件的特徵尺寸不斷縮小的情況下，使得現有的理論觀念已不能用來解釋其效應特性。所以我們必須做出新的嘗試。近期磁性材料FePt在應用上的潛力受到關注，其具有相當大的晶格異相性、飽和磁化量以及熱穩定性。故我們將其圖案化並嵌入二極體元件中，探討其電性的變化。 本論文內容主要分成三個部分，第一部份設計基本PN二極體結構，利用佈值後退火當作變因，以達到有基本逆向飽和電流為目標。第二部份會嵌入奈米磁鐵FePt，探討奈米磁鐵FePt對PN二極體的磁電特性。第三部份將會配合磁退火系統，在外加磁場下進行高溫退火，使奈米磁鐵FePt具有高方向性磁場，並尋找最佳的磁化條件。本論文的重點將會是研究奈米磁鐵FePt對PN二極體的電性影響。

“Diode” has so far been widely applied in the Very-large-scale integration (VLSI). What is more, the theorem and characteristics of its device also lay a solid foundation for the device of semiconductor. Nowadays, the feature size of semiconductor has been downsized, which makes the theories insufficient to explain both its effect and property. Therefore, we have to make a new attempt. Recently, there has been a lot of attention on magnetic material’s potential. FePt has been selected since it’s magnetocrystalline anisotropy and saturated magnetization is larger than other magnetic materials and chemical stability is better than others. Because of that, we embed FePt to PN diode and study its magneto-electric coupling effect on breakdown voltage and reverse saturated current. There are three parts of this thesis. First part is the fabrication of PN diode structures. By making the temperature of after implant annealing to be the variables, we try to find the basic reverse leakage current. In the second part we embed nano-magnet FePt to PN diode and investigates the electrical and magnetic characteristic effect of PN diode which is affected by FePt nano-magnets. We observed lower reverse leakage current and higher breakdown voltage of PN diode which embedded nano-magnet FePt. In the last part, we use magnetic annealing which is in a strong external magnetic field to find the optimal condition. According to theoretical predictions, the magnetic field can reduce leakage current and enhance the breakdown voltage. And magnetic annealing process can enhance remanent magnetization and saturated magnetization of devices. So we use magnetic annealing process to increase saturated magnetization and we will get better electrical characteristics.