Effect of low temperature RF plasma treatment on electrical properties of junctionless InGaAs MOSFETs

In this paper, we study the effect of low-temperature RF plasma treatment in forming gas (10%H2+90%N2) on the electrical characteristics of junctionless MOSFETs with n-In0.53Ga0.47As channel and an Al2O3 gate dielectric. The impact of plasma power density on the device parameters is investigated. It is found that RF plasma annealing with a low power density (0.5 W/cm2) at 150°C for 10 min provides substantial improvement of source/drain contacts resistance and the carrier mobility resulting in a considerable increase of the on-state current and transconductance. It also improves the subthreshold slope and reduces the fixed positive charge in Al2O3 under the gate, shifting the threshold voltage toward positive values. It is demonstrated that non-thermal factors play a principle role in modification of electrical properties of the JL MOSFETs under RF plasma treatment. Such treatment may be an efficient tool for the improvement of the performance of the advanced MOSFETs with III-V channel materials

Surface reconstruction and optical absorption changes for Ge nanoclusters grown on chemically oxidized Si(1 0 0) surfaces

International audienceGermanium (Ge) nanoclusters are grown by a molecular-beam epitaxy technique on the chemically oxidized Si(1 0 0) surface at 700 °C. X-ray diffraction and photocurrent spectroscopy demonstrate that the nanoclusters have the local structure of body-centred-tetragonal Ge, exhibiting an optical adsorption edge at 0.48 eV at 50 K. Deposition of silicon on the surface with Ge nanoclusters leads to surface reconstruction and formation of polycrystalline diamond-like Si coverage, while nanoclusters' core becomes tetragonal SiGe alloy. The intrinsic absorption edge is shifted to 0.73 eV due to Si–Ge intermixing. Possible mechanisms for nanoclusters growth are discussed

Electrical properties of LaLuO3/Si(100) structures prepared by molecular beam deposition

The paper presents the results of electrical characterization in the wide temperature range (120-320 K) of the interface and bulk properties of high-k LaLuO3 dielectric deposited by molecular beam deposition (MBD) on silicon substrate. The energy distribution of interface state density is presented and typical maxima of 1.2 71011 and 2.5 710 11 eV-1 cm-2 were found at about 0.25-0.3 eV from the silicon valence band. The charge carrier transport through the dielectric at the forward bias was found to occur via Poole-Frenkel mechanism, while variable range hopping conduction (Mott\u27s law) controls the current at the reverse bias