Temperature Dependent Carrier Lifetime, Diffusion Coefficient, and Diffusion Length in Ge0.95Sn0.05 Epilayer
Journal of Applied Physics 2020
P. Ščajev, V. Soriūtė, G. Kreiza, T. Malinauskas, S. Stanionytė, Pāvels Onufrijevs, Artūrs Medvids, H. Cheng

The development of new technology, which would be able to shift photosensitivity of Si devices to the mid-infrared range, preserving the benefits of cheap silicon readout circuits, is of high priority for short-wave infrared photo-detection in defense, medical, night vision, and material production applications. Group IV GeSn-based materials have recently shown promising optoelectronic characteristics, allowing extension of the detection range to the mid-infrared region. However, the electronic properties of the material are not well understood and need further research. In this work, we provide temperature dependent studies of carrier lifetime, diffusion coefficient, and diffusion length in Ge0.95Sn0.05 epilayer on silicon by applying contactless light induced transient grating technique. The observed temperature dependence of lifetime was explained by the recombination of carriers on vacancy-related defects. The electron and hole capture cross sections were calculated. The temperature dependence of the diffusion coefficient indicated hole mobility limited by phonon and defect scattering. Weakly temperature dependent diffusion length of ∼0.5 μm verified material suitability for efficient submicrometer-thick optoelectronic devices.


DOI
10.1063/5.0019861
Hyperlink
https://aip.scitation.org/doi/pdf/10.1063/5.0019861

Ščajev, P., Soriūtė, V., Kreiza, G., Malinauskas, T., Stanionytė, S., Onufrijevs, P., Medvids, A., Cheng, H. Temperature Dependent Carrier Lifetime, Diffusion Coefficient, and Diffusion Length in Ge0.95Sn0.05 Epilayer. Journal of Applied Physics, 2020, Vol. 128, No. 11, Article number 115103. ISSN 0021-8979. Available from: doi:10.1063/5.0019861

Publication language
English (en)
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