Low thermal budget epitaxial lift off (ELO) for Ge (111)-on-insulator structure

Abstract

Germanium-on-Insulator (GeOI) structures with the surface orientation of (111) have been successfully fabricated by using low thermal budget epitaxial-lift-off (ELO) technology via direct bonding and selective etching. The material characteristics and transport properties of the Ge(111)OI structure have been systematically investigated through secondary-ion mass spectrometry, Raman spectroscopy, X-ray diffraction, high-resolution transmission electron microscope, and Hall measurement. The transferred Ge (111) layer remained almost intact from the as-grown epitaxial layers, indicating the benefits of ELO technology. The low thermal budget ELO technology demonstrated in this work is promising to integrate Ge channels with different surface orientations on Si (100) substrates for future monolithic 3D applications.

Wafer-scale detachable monocrystalline germanium nanomembranes for the growth of III–V materials and substrate reuse

“…Another technique called Epitaxial li-off of layers (ELO) uses a sacricial layer with selective chemical etching to grow and release the "active" epitaxial structure. 18,19 However, this etching process is extremely slow and can take tens of hours at the wafer-scale, which is a major drawback of this method. Another technique that has emerged in this eld is controlled spalling.…”