Defect states in strain-relaxed Si0.7Ge0.3 layers grown at low temperature
Defect states in strain-relaxed Si0.7Ge0.3 layers grown at low temperature
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低温生长的应变松弛 Si0.7Ge0.3 层中的缺陷态
DOI：
10.1063/1.365599
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发表时间：
1997
影响因子：
3.2
通讯作者：
B. Meyerson
中科院分区：
文献类型：
--
作者：
P. Mooney;L. Tilly;C. D'Emic;J. Chu;F. Cardone;F. Legoues;B. Meyerson
在Si（100）衬底上，采用双真空化学气相沉积法生长的应变弛豫Si_（0.7）Ge_（0.3）薄膜，在~ 560 °C的温度下，深能级瞬态谱（DLTS）数据主要由两个浅空穴陷阱组成。陷阱能级为Ev+0.06和Ev+0.14 eV，在弛豫层中陷阱浓度为1.5 ×1014 cm−3，穿透位错密度为2-4×107 cm−2。填充率的对数依赖性表明，这些陷阱与扩展的缺陷，这是证实了它们的情况下，在样品中没有位错。DLTS峰的退火温度与这些陷阱作为位错处的缺陷复合物的状态的解释是一致的，而不是本征位错状态或孤立的缺陷复合物。陷阱浓度与膜中的氧浓度成比例，表明氧可能是缺陷复合物的成分。
Two shallow hole traps dominate the deep level transient spectroscopy (DLTS) data for strain-relaxed Si0.7Ge0.3 layers grown on Si(100) by ultrahigh vacuum chemical vapor deposition at temperatures ⩽560 °C. The trap energy levels are at Ev+0.06 and Ev+0.14 eV and trap concentrations are ⩽5×1014 cm−3 in relaxed layers having threading dislocation densities of 2–4×107 cm−2. A logarithmic dependence of the filling rate indicates that these traps are associated with extended defects and this is confirmed by their absence in a sample having no dislocations. The annealing temperature of the DLTS peaks is consistent with the interpretation of these traps as states of defect complexes at dislocations, rather than intrinsic dislocation states or isolated defect complexes. The trap concentrations are proportional to the oxygen concentration in the film, suggesting that oxygen may be a constituent of the defect complex.