Synthesis of Oxide Interface-Based Two-Dimensional Electron Gas on Si

Two-dimensional electron gas (2DEG) at the interface of amorphous Al2O3/SrTiO3 (aAO/STO) heterostruc-tures has received considerable attention owing to its convenience of fabrication and relatively high mobility. The integration of these 2DEG heterostructures on a silicon wafer is highly desired for electronic applications but remains challanging up to date. Here, conductive aAO/STO heterostructures have been synthesized on a silicon wafer via a growth-and-transfer method. A scanning transmission electron microscopy image shows flat and close contact between STO membranes and a Si wafer. Electron energy loss spectroscopic measurements reveal the interfacial Ti valence state evolution, which identifies the formation of 2D charge carriers confined at the interface of aAO/STO. This work provides a feasible strategy for the integration of 2DEG on a silicon wafer and other desired substrates for potential functional and flexible electronic devices.

Automated summary

Conductive amorphous Al2O3/SrTiO3 heterostructures have been successfully synthesized on a silicon wafer through a growth-and-transfer method. The formation of a two-dimensional electron gas (2DEG) at the interface of aAO/STO has been confirmed through electron energy loss spectroscopic measurements. This work provides a feasible strategy for integrating 2DEG on a silicon wafer and other desired substrates, with potential significance for functional and flexible electronic devices.