利用掃描穿隧顯微鏡觀察鉛於矽(100)-2×1表面之相變

Abstract

藉由超高真空顯微鏡,我們可以觀察到鉛在低溫及室溫鍍在矽(100)-2x1表面之行為. 在低溫成長過程中,隨著鉛鍍量由0.3ML增加到3ML,我們臨場觀察到表面重構會由(2x2)依序變化為(2x1)最後形成(4x4)與一亞穩相共存的結構. 而此亞穩態結構會逐漸轉換成c(4x4)隨著溫度逐漸升高到室溫. 我們將以一系列STM影像來證明此相變過程. 此外,我們並嘗試建立該亞穩態的原子模型.

The behavior of Pb deposited on a Si(100)-2×1 surface at room temperature and low temperature was observed by ultrahigh vacuum scanning tunneling microscope. Low temperature phases of (2×2), (2×1), (4×4) and a new “meta-stable phase” were identified as Pb coverage was increased from 0.3 to about 3ML. As the temperature is continuously increased to room temperature, the meta-stable phase is transformed into c(4×4) phase. We have made a STM movie to proof this phase transition. Moreover, we have constructed an atomic model of the meta-stable phase.