Strain Relaxation at Semiconductor Surface Revealed by X-Ray Diffraction

X 射线衍射揭示半导体表面的应变弛豫

• 批准号: 12440086
• 负责人: AKIMOTO Koichi
• 金额: $ 6.78万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12440086/
• 关键词: Surface; X-Ray Diffraction; Strain Relaxation; Reconstructed Surface; Dynamical Theory; Synchrotron Radiation; 再構成構造

Extremely asymmetric X-ray diffraction is a noble method to evaluate strain fields near crystal surfaces or interfaces. This method is sensitive to crystal structure near surface region because a glancing angle of X-ray is set near a critical angle of total reflection. A minute strain fields (【greater than or equal】 0.1%) at surface brings a variation of intensity and width of rocking curves. Therefore we can evaluate strain near surfaces by analyzing curve-shape or integrated intensity of the curves. We show two examples of experimental strain evaluation. One is Si reconstructed surfaces. We evaluated intrinsic strain fields near Si reconstructed surfaces, i.e., Si(111)-(7×7), Si(111)-(√<3>×√<3>)-Al, and Si(111)-(√<3>×√<3>)-Ag surfaces, in quantitatively. From the fitting of the experimental rocking curves with calculated curves, we found that all reconstructed surfaces bring a contraction of the (111) spacing due to surface lattice relaxation, and such strain extends to some ten nm under the surfaces. Another example is silicide surfaces. We evaluated a strain evolution near hydrogen-terminated Si(111) surface due to nickel deposition. We found that a compressive strain gradually introduces into the substrate accompany with a growth of "Ni diffusion layer" near the hydrogen-terminated surface.

极不对称X射线衍射是一种评估晶体表面或界面附近应变场的有效方法。由于X射线的掠射角设置在全反射的临界角附近，因此该方法对近表面区域的晶体结构敏感。表面微小应变场（≥ 0.1%）引起摇摆曲线强度和宽度的变化。因此，可以通过分析曲线形状或曲线的积分强度来评估表面附近的应变。我们展示了两个实验应变评估的例子。一种是Si重构曲面。我们评估了Si重建表面附近的本征应变场，即，Si（111）-（7×7）、Si（111）-（111 <3>× <3>104）-Al和Si（111）-（<3>111 × 104<3>）-Ag表面的显微结构。通过对实验摇摆曲线与计算曲线的拟合，我们发现由于表面晶格弛豫，所有重构表面的（111）面间距都发生了收缩，这种应变延伸到表面下约10 nm处。另一个例子是硅化物表面。我们评估了由于镍沉积导致的氢端Si（111）表面附近的应变演化。我们发现，随着氢终止表面附近“Ni扩散层”的生长，压应变逐渐引入到衬底中。

项目成果

T. Emoto: "Quantitative Evaluation of Strain near Reconstructed Si Surface"Surface Science. 493. 221-226 (2001)

T. Emoto：“重建硅表面附近应变的定量评估”表面科学。

S. Horii: "Interface Reconstructed Structure of Ag/Si(111) Revealed by X-ray Diffraction"Surface Science. 493. 194-199 (2001)

S. Horii：“X 射线衍射揭示的 Ag/Si(111) 界面重构结构”表面科学。

T.Emoto: "Quantitative Evaluation of Strain near Reconstructed Si Surface"Surface Science. 493. 221-226 (2001)

T.Emoto：“重建硅表面附近应变的定量评估”表面科学。

A.Hata, K.Akimoto, S.Horii, T.Emoto, A.Ichimiya, H.Tajiri, T.Takahashi, H.Sugiyama, X.Zhang, and H.Kawata: "Crystal Orientation of Silver Films on Silicon Surfaces Revealed by Surface X-ray Diffraction"Surf.Rev.Lett.. to be published. (2003)

A.Hata、K.Akimoto、S.Horii、T.Emoto、A.Ichimiya、H.Tajiri、T.Takahashi、H.Sugiyama、X.Zhang 和 H.Kawata：“硅表面银膜的晶体取向”

T.Emoto: "Strain near SiO_2-Si interface revealed by X-ray diffraction intensity enhancement"Thin Solid Films. 369・1&2. 281-284 (2000)

T.Emoto：“通过X射线衍射强度增强揭示SiO_2-Si界面附近的应变”Thin Solid Films 369・1&2（2000）。