摘要
利用同步辐射光电子能谱研究了Ｋ在ｐ型ＩｎＰ（１００）表面的吸附及其界面反应．由Ｋ吸附过程中Ｉｎ４ｄ和Ｐ２ｐ芯能级谱的变化发现：在碱金属Ｋ吸附于ｐ型ＩｎＰ（１００）表面的过程中，Ｋ—Ｐ之间发生了化学反应，形成Ｋ—Ｐ化合物，当Ｋ覆盖度０＞２１０Ｓｅｃ时稳定的Ｋ—Ｐ化合物基本形成，此时Ｐ２ｐ峰的峰形和峰位基本保持不变．Ｋ—Ｉｎ之间无明显的化学反应发生，但在Ｋ的吸附过程中，碱金属Ｋ对Ｉｎ有置换反应发生，使Ｉｎ偏析到ＩｎＰ（１００）的表面．ＩｎＰ（１００）表面的Ｋ吸附层引起了能带弯曲．能带弯曲的值为０．７５ｅＶ．偏析到ＩｎＰ（１００）表面的Ｉｎ的悬挂键空态被来自于碱金属Ｋ的外层电子所填充，形成一个半满的表面态．正是这个半满的表面态是引起能带弯曲和Ｆｅｒｍｉ能级钉扎。
Abstract The room temperature adsorption of K on p-type InP(100) has been studied with use of synchrotron radiation core-level spectroscopy. From the coverage dependent In 4d and P 2p core-level spectra, we found that in the process or K adsorption on InP(100), the reaction between K and P is observed and K-P compound is formed. When the K coverage 0 > 210 Sec.,the stable K-P compound is formed. Meanwhile, the peak position and peak shape of P 2p shows no change. No reaction occurs between K and In, and in the process of K adsorption on InP(100) surface, the in of substrate is exchanged into surface by K. The K adsorption leads to band bending: The empty state of dangling bond of in (exchanged by K) was filled by the our-shell electrons of K, formed a half-filled surface state. The fermi-level shift and pinning was caused by this half-filled surface state.
基金
国家自然科学基金
