Metal-oxide-semiconductor devices with molecular beam epitaxy-grown Y2O3 on Ge
Journal
Journal of Crystal Growth
Journal Volume
311
Journal Issue
7
Pages
2195-2198
Date Issued
2009
Author(s)
Abstract
Excellent electrical performance has been achieved on Ge metal-oxide-semiconductor (MOS) devices using molecular beam epitaxy (MBE)-deposited dielectrics of Al2O3/Y2O3 directly on Ge(1 0 0) without utilizing any interfacial layers, such as GeOxNy or Si. Slight Ge diffusion into Y2O3 was observed using in-situ X-ray photoelectron spectroscopy. The interface between Y2O3 and Ge is atomically smooth after a high-temperature anneal at 500 °C for 10 min as characterized using high-resolution transmission electron microscopy. A high κ value of Y2O3 of ∼17.3 and a low gate leakage current density of 7.6×10-9 A/cm2 have been obtained from the MOS capacitors with a total capacitance equivalent thickness (CET) of 2.41 nm. Furthermore, ring-type p-channel MOS field-effect transistors with the same gate oxides have exhibited a high drain current density of 98 mA/mm, a peak transconductance of 43 mS/mm, and a hole mobility of 241 cm2/V s with a gate length and a gate width of 4 and 400 μm, respectively. © 2008 Elsevier B.V. All rights reserved.
SDGs
Type
journal article