研究水分子在氯化鈉/鍺(100)表面之化學反應

Abstract

本文討論H2O在1ML NaCl/Ge(100)-(2□1)上的化學反應與加熱反應。在室溫下Ge(100)表面上利用分子束磊晶蒸鍍1ML NaCl，接著於NaCl/Ge(100)表面曝18000L H2O，最後再加熱，以核心層光電子激發術觀察樣品表面的原分子反應過程。由Ge 3d和Cl 2p光電子強度可知NaCl有Cl-Ge的鍵結產生，曝H2O後，有OH-Ge的鍵結產生，Ge dangling bond的光電子強度減少且出現GeO1+的光電子強度。接著，也觀察到Na 2p和Cl 2p的束縛能有減少約0.3 eV的現象，代表H2O與Ge dangling bond對於表面上NaCl的影響。最後加熱樣品，發現Na 2p和Cl 2p的束縛能有回復到未曝水NaCl的狀態且鍺塊材的強度有明顯增加現象而Na 2p和Cl 2p強度明顯有降低，表示有部份H2O及NaCl脫附於Ge(100)表面。而由光電子強度發現，GeO1+並沒有脫附表面的情況發生。

This article discuss water exposing on 1ML NaCl/Ge(100) sample for reacting and annealing observation. In RT, we use MBE to expose NaCl on clean Ge(100) surface. Then, use leak valve to expose water on sample. Finally, annealing sample and use the XPS to study surface behavior. For spectrum, we find Cl-Ge bond on Gemanium surface. After exposing water, we are not only observing Ge+ intensity increse but also Ge monoxide intensity.For binding energy, Sodium and Chlorine decrese about 0.3 eV. Finally, Water, Sodium and Chlorine desorb by annealing, but Ge monoxide doesn’t change.Also, we find binding energy change from Sodium and Chlorine state to Sodium-Chlorine state.