Abstract The best way to produce silicon-based Ge infrared detectors with lower dark current density is to develop high-quality buffer layers with low dislocation density and high relaxation degree. In this paper, we grew both Ge/Si and Si 1 − x Ge x /Si heterostructures and studied the effects of Ge composition, annealing-influenced dislocation density, and strain relaxation. Using high-resolution X-ray diffraction and swing curve (224) analysis, we found that the thin films after annealing exhibited strain relaxation of > 90%. Their dislocation density was lower than 8.0 × 10 5 /cm 2 , while their average roughness was 1.4–2.0 nm. These results show that such heterostructure buffer layers can be used to produce Ge-alloy infrared photodetectors with good performance.

中文翻译：

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SiGe/Si异质结构的微观结构和光电性能

摘要 研制低位错密度和高弛豫度的高质量缓冲层是制备具有较低暗电流密度的硅基锗红外探测器的最佳途径。在本文中，我们生长了 Ge/Si 和 Si 1 - x Ge x /Si 异质结构，并研究了 Ge 成分、退火影响的位错密度和应变弛豫的影响。使用高分辨率 X 射线衍射和摆动曲线 (224) 分析，我们发现退火后的薄膜表现出> 90% 的应变松弛。它们的位错密度低于8.0 × 10 5 /cm 2 ，而它们的平均粗糙度为1.4-2.0 nm。这些结果表明，这种异质结构缓冲层可用于生产性能良好的锗合金红外光电探测器。