超高真空系統架設與鐵在低溫下成長於金與矽基板之研究

Abstract

我們建立了一部多功能超高真空系統，其背景壓力約在3x10^-10托耳。而用電子穿隧掃描顯微鏡來觀測樣品所得到的表面形貌圖片可以藉由石墨和單晶矽基板來校正。在180K將鐵成長於金(111)表面的系統中，發現有雙生的核成長在金(111)重構表面fcc結構的紐節處，這和在90K曝氙成長的結果非常不一樣。當再一次鍍膜於180K，使膜厚度達0.45個原子層後再以室溫退火處理，發現金的奈米顆粒成長呈現隨機分布。而在金(111)的面上有些區域呈現與面(111)相鄰斜面的結構，鐵在此相鄰結構上的成長和另一個相鄰面，金(788)面，的系統完全不一樣。最後，我們同時建置了磁光柯爾效應量測裝置，其最大磁場可達4300高斯。同時我們也成功的量測到鐵薄膜在矽基板平面方向的磁滯曲線。

The UHV system in C207 in the Department of physics, NTNU was established with the best base pressure lower than 3x10^-10 torr. The image of STM can be corrected by Si(111) 7 x 7 and HOPG. The morphology of the growth of Fe on Au(111) herringbone surface at low temperature (LT) has been investigated. When depositing Fe on Au(111) herringbone surface at 180 K, doublets are uniformly located on fcc sites, that is dierent from the result of room temperature (RT) growth and exposure xenon at 90 K. After a repeat of 180 K deposition and RT annealing with total thickness of 0.45 ML, Fe clusters become random, and the 300 K annealing efect is not obvious. On the Au(111) surface, there is a region presenting a vicinal-like surface stucture, on which the Fe growth is totally diferent from the published results on Au(788) vicinal surface, the location of some small Fe clusters. Finally, the MOKE was set up with max field of 4000 Gauss. And we successfully obsreved the hyteresis loop of Fe/Si(111) in in-plane magnetization.