Infrared spectra of hydrogen bound to group-III acceptors in Si: Homogeneous line broadening and sidebands
Infrared spectra of hydrogen bound to group-III acceptors in Si: Homogeneous line broadening and sidebands
复制标题
与 Si 中第 III 族受体结合的氢的红外光谱：均匀线展宽和边带
DOI：
10.1103/physrevb.65.075214
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发表时间：
2002
影响因子：
3.7
通讯作者：
H. Yamada‐Kaneta
中科院分区：
文献类型：
--
作者：
M. Suezawa;N. Fukata;M. Saito;H. Yamada‐Kaneta
本文报道了硅中第三族受主束缚氢原子的局域振动光谱特征。为了避免Fano效应对谱线展宽的影响，我们用III族受体和低浓度的氢均匀掺杂样品;因此，用洛伦兹函数很好地拟合了谱线形状，表明谱线形状受到两种动力学效应的影响，即，能量弛豫和失相。而B-H，Al-H和Ga-H对的光谱被发现只显示一个边带在主峰的低频区域，边带出现在低和高频率区域的情况下，在In-H。在In-H对的情况下，边带的这种出现是先前模型所没有预料到的[M. Stavola等人，物理评论B 37，8313（1988）]。通过分析主峰在6 K附近的线宽，我们估计的能量弛豫时间T1，这被发现是比以前观察到的点缺陷和在Si中的H的复合物短得多。此外，我们还发现了一个化学趋势：随着III族受体共价半径的增加，T1变得更短。基于退相模型，分析了主峰的线宽和峰位移随温度的变化关系。分析表明，在局域振动模与hath振动模之间的非谐耦合的弱耦合极限下，实验结果不能用Reisson-Ryberg模型解释，表明非谐耦合是中等或强的。
We report spectral features of localized vibration of hydrogen bound to group-III acceptors in Si. To avoid the Fano effect on the line broadening, we homogeneously doped specimens with group-III acceptors and hydrogen with low concentrations; consequently, the line shapes were well fitted by Lorentzian functions, indicating that the shapes were affected by two dynamical effects, i.e., energy relaxation and dephasing. While the spectra of B-H, Al-H and Ga-H pairs were found to show only one sideband in the lower-frequency region of the main peak, sidebands appeared in both the lower-and higher-frequency regions in the case of In-H. This appearance of the sidebands in the case of In-H pairs was unexpected from a previous model [M. Stavola et al., Phys. Rev. B 37, 8313 (1988)]. By analyzing the linewidth of the main peak at around 6 K, we estimated the energy relaxation times T 1 , which were found to be much shorter than those previously observed for the complexes of the point defect and H in Si. Moreover, we also found a chemical trend: As the covalent radius of the group-III acceptor increased, the T 1 became shorter. Temperature dependences of the linewidth and peak shift of the main peak were analyzed based on dephasing models. The analysis showed that the experimental results cannot be explained by the Persson-Ryberg model in the weak-coupling limit of the anharmonic coupling between the local vibrational mode and hath ones, suggesting that the anharmonic coupling is intermediate or strong.