Effect of subphase pH on Langmuir-Blodgett deposition of graphene oxide monolayers on Si and SiO 2 /Si substrates AIP Conf. Proc. 1512, 708 (2013); 10.1063/1.4791234 Reduced graphene oxide produced by rapid-heating reduction and its use in carbon-based field-effect transistors J. Appl. Phys. 112, 033701 (2012); 10.1063/1.4739486 High-yield dielectrophoretic assembly of two-dimensional graphene nanostructures Appl. Phys. Lett. 94, 053110 (2009);

No abstract

No abstract

Articles you may be interested inGe-stabilized tetragonal ZrO 2 as gate dielectric for Ge metal-oxide-semiconductor capacitors fabricated on Si substrate Appl. Phys. Lett. 97, 043503 (2010); 10.1063/1.3455904Damage-free metal-oxide-semiconductor gate electrode patterning on thin HfSiON film using neutral beam etching J.

We have developed a hygromorphic metal oxide actuator using an electrochemical method to produce a superhydrophilic freestanding nano-capillary forest of titanium oxide with a high aspect ratio (~80). This metal oxide film has an inhomogeneous initial gap at the top and bottom surfaces between the tubes due to flexure during fabrication. The actuation mechanism is as follows. First, when a drop of water is applied on the surface of a titanium oxide nano-capillary forest (TNF), the water penetrates through the film instantaneously, and the titanium oxide nano-capillaries are pulled together by interplay of the capillary force and van der Waals force. When water has fully filled in the gaps between the capillaries, the free-standing TNF film remains unbent for~2 min. Then, as the water evaporates, the film bends further in the forward direction. When the water has completely evaporated, the van der Waals force alone acts on the capillaries, and the TNF film returns to its initial state. This TNF possesses great stability and repeatability for long-term usage having a high bending energy density of~1250 kJ m -3 and unique capabilities. It may lead to novel stimuli-responsive systems, including energy collection and storage, as well as robotics applications.

We have investigated the effects of high temperature annealing on the physical and electrical properties of multilayered high-k gate oxide [HfSixOy/HfO2/intermixed-layer(IL)/ZrO2/intermixed-layer(IL)/HfO2] in metal-oxide-semiconductor device. The multilayered high-k films were formed after oxidizing the Hf/Zr/Hf films deposited directly on the Si substrate. The subsequent N2 annealing at high temperature (⩾ 700 °C) not only results in the polycrystallization of the multilayered high-k films, but also causes the diffusion of Zr. The latter transforms the HfSixOy/HfO2/IL/ZrO2/IL/HfO2 film into the Zr-doped HfO2 film, and improves electrical properties in general. However, the thin SiOx interfacial layer starts to form if annealing temperature increases over 700 °C, deteriorating the equivalent oxide thickness.

Properties of the HfO2/Hf-silicate/Si structure with the Hf-silicate layer which was formed by Hf metal deposition on Si and subsequent reaction of Hf with Si and oxygen during the HfO2 deposition were studied. Post-deposition N2 annealing reduced the equivalent oxide thickness (EOT) value and improved leakage characteristics of the HfO2/Hf-silicate/Si structure. The EOT value was reduced from 2.70 nm to 2.23 nm after annealing. At a proper voltage of 2.5 V, which was defined as the difference between the applied gate bias and the flat band voltage, the leakage current density of annealed HfO2/Hf-silicate/Si structure was 1.88×10-7 A/cm2 while that of as-formed HfO2/Hf-silicate/Si structure was 1.92×10-6 A/cm2. The breakdown field increased from 7.29 MV/cm to 9.71 MV/cm after annealing.

The interfacial reaction between poly Si 1Ϫx Ge x (x ϭ 0, 0.2, 0.4) and ZrO 2 films after annealing was investigated to use ZrO 2 films as an alternative gate dielectric. In the poly Si/ZrO 2 structure, silicidation was the dominant reaction due to continuous formation of Zr-silicide and SiO during annealing. However, in poly Si 1Ϫx Ge x (x ϭ 0.2, 0.4)/ZrO 2 , silicate formation was the main reaction after annealing at 900°C for 30 min. In addition, after annealing at 800°C, the silicate layer was observed only in the poly Si 0.6 Ge 0.4 /ZrO 2 system.