Development of atomic-scale materials processing utilizing electron-beam induced selective chemical reaction

主要研究成果如下：(1)阐明了Al2Cl6分子吸附的初始阶段，其中静止原子在吸附过程中起着重要作用。A12C16分子在吸附时分解，导致氯和AlClx分子优先吸附在中心吸附原子上。在此基础上，证明了吸附的单个氯原子和AlClx分子的解吸作用。我们还成功地完成了分子的置换和分子的分解，导致了铝原子的吸附。(2)用扫描电子显微镜研究了Hf处理的Si(111)表面的局域原子结构。在此基础上，通过在针尖和样品表面之间施加电压脉冲，在(C2H5)3GA吸附的Hf处理的Si(111)表面上沉积了Ga纳米点。其基本机理是尖端以下吸附的(C2H5)3GA分子的电场增强分解。(3)阐明了吸附Al的Si(111)表面的局域原子结构和Si固相外延过程中的原子过程。

The main results obtained in this project are summarized as follows : (1) The initial stages of the adsorption of Al2Cl6 molecules are elucidated, in which rest atoms play an important role in the adsorption process. An A12C16 molecule decomposes on adsorbtion, resulting in the preferential adsorption of Cl and AlClx molecules onto the center adatom. Based on these findings, the desorptin of adsorbed single Cl atom and AlClx molecule is demonstrated. We succeeded also in the displacemnet of the molecule and the decomposition of the molucule, resulting in the adsorption of an Al atom. (2) Local atomic structures of HF-treated Si (111) surfaces are elucidated using STM.Based on this study, Ga nano dots are deposited onto (C2H5) 3Ga-adsorbed HF-treated Si (111) surfaces by appling a voltage pulse between the tip and the sample surface. The underlying mechansism is the electric-field enhanced decompositin of the adsorbed (C2H5) 3Ga molecule below the tip. (3) Local atomic structures of Al-adsorbed Si (111) surfaces and atomistic processes during Si solid phase epitaxy are elucidated.