We report a comparative study of metamorphic InAs p-i-n photodetectors epitaxially grown on GaAs and Si by molecular beam epitaxy. Linearly graded InAlAs buffers were employed to bridge the high lattice mismatch between InAs and Si. Quantitative measurement for threading dislocation density (TDD) in the InAs layers grown on GaAs and Si has been performed using transmission electron microscopy and electron channeling contrast imaging, both of which revealed that the TDD of InAs/Si sample is ~35% higher than that of GaAs sample. Comparison of fabricated InAs p-i-n photodetectors indicated that reduction of threading dislocation density is crucial for low dark current and high responsivity mid-infrared photodetectors on Si.

我们报告了通过分子束外延在GaAs和Si上外延生长的变质InAs pin光电探测器的比较研究。采用线性分级的InAlAs缓冲液来弥合InAs和Si之间的高晶格失配。使用透射电子显微镜和电子通道对比度成像技术对GaAs和Si上生长的InAs层中的螺纹位错密度（TDD）进行了定量测量，这两者均表明InAs / Si样品的TDD比TDS高约35％。砷化镓样品。比较制成的InAs引脚光电探测器表明，降低线错位密度对于Si上的低暗电流和高响应度的中红外光电探测器至关重要。