Unraveling the Mechanism of Remote Scavenging Effect at the InP/Al2O3 Interface Induced by Titanium Layer

Low interface oxide concentration is desired for III-V semiconductor/high k dielectrics stacks to get high-performance devices. The remote scavenging effect is observed upon Ti metal deposition on the InP/Al2O3 system, characterized by in situ angle resolved X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry, as well as ex situ cross-sectional transmission electron microscopy. The mechanism is investigated by O-18 tracing. Two mechanisms are proposed for this remote scavenging effect. The impact of this remote scavenging effect is studied by metal oxide semiconductor (MOS) capacitors fabrication and characterization. This work sheds light on InP-based MOS devices.