An overview is given on recent advances of science and devices of III-V based and Si MOS and MOSFET. Firstly, we have integrated molecular beam epitaxy (MBE) with atomic layer deposition (ALD) for the growth of excellent high-kappa dielectrics with abrupt interfaces, critical for further complementary metaloxide-semiconductor (CMOS) scaling beyond the 45 nm node. Secondly, we showed that epitaxial yttrium-doped HfO2 films on GaAs(1 0 0) have stabilized the cubic phase, and led to enhancement of kappa over 30. Thirdly, inelastic electron tunneling spectroscopy (IETS) was applied to probe the phonon modes and charge trappings within the high-kappa dielectrics. Fourthly, scaling of the high-kappa oxides approaching 1.0 nm capacitance equivalent thickness (CET) is achieved in a Ga2O3(Gd2O3)[GGO]/ In0.2Ga0.8As (InGaAs) gate stack that has undergone 850 degrees C rapid thermal annealing, and which has unpinned the surface Fermi level of the III-V semiconductor. Finally, we have demonstrated a selfaligned inversion-channel In0.53Ga0.47As MOSFETs made of Al2O3(2 nm)/GGO(7 nm) gate oxide and TiN metal gate at 1-mu m gate length, reaching a world record of drain current and transconductance. (C) 2008 Elsevier B.V. All rights reserved.