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arXiv · 1705.06832

Highly strained Ge micro-blocks bonded on Si platform for Mid-Infrared photonic applications

Alban Gassenq·Kevin Guilloy·Nicolas Pauc·Denis Rouchon·Julie Widiez·Johan Rothman·Jean-Michel Hartmann·Alexei Chelnokov·Vincent Reboud·Vincent Calvo
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Abstract

Adding sufficient tensile strain to Ge can turn the material to a direct bandgap group IV semiconductor emitting in the mid-infrared wavelength range. However, highly strained-Ge cannot be directly grown on Si due to its large lattice mismatch. In this work, we have developed a process based on Ge micro-bridge strain redistribution intentionally landed to the Si substrate. Traction arms can be then partially etched to keep only localized strained-Ge micro-blocks. Large tunable uniaxial stresses up to 4.2% strain were demonstrated bonded on Si. Our approach allows to envision integrated strained-Ge on Si platform for mid-infrared integrated optics.

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Alban Gassenq, Kevin Guilloy, Nicolas Pauc, Denis Rouchon, Julie Widiez, Johan Rothman, Jean-Michel Hartmann, Alexei Chelnokov, Vincent Reboud, Vincent Calvo. 2017-05-18. Highly strained Ge micro-blocks bonded on Si platform for Mid-Infrared photonic applications. https://arxiv.org/abs/1705.06832

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