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The structural and electrical properties of boron doped amorphous silicon-germanium alloy films, obtained using a low frequency plasma enhanced chemical vapor deposition (LF PECVD), are presented in this contribution. These thin films were deposited on a substrate heated at 270°C, and by decomposing a mixture of silane, germane, and diborane gases. The chemical bond structure was studied by Infrared Spectroscopy. Our results show that, for a constant diborane flow, the increase of germane flow enhances the incorporation of boron into the film; the peak at 2540 cm -1 becomes larger as the Ge content increases. Transport of carriers was studied by measuring current-voltage curves as a function of temperature. The conductivity increased from 10 -6 to 10 (Ω-cm) -1 , while the refraction index increased from 3.312 to 4.4458, for an increasing Ge content; this makes the films suitable for optical waveguide applications. On the other hand, the activation energy varied from 0.668 to 0.220 eV when the sample was doped with boron. The AFM images showed that the surface roughness was improved for an alloy with 50% of Ge.

In this work we present the design and fabrication of a test chip to be used for the characterization of the main electrical, mechanical and thermal properties of the structural materials involved in the development of polysilicon-based electrothermal actuators. With this combined bulk/surface micromachined chip, parameters such as Young's modulus (E), stretching or compression stresses (±σ), stress gradients (± Δε), electrical resistivity (ρe), doping level (n+), thermal conductivity (κ), and thermal capacitance (C) can be obtained. This test chip was fabricated using the PolyMEMS-INAOE fabrication process, in which the main materials involved are silicon oxide, silicon nitride, phosphosilicate glass, aluminum, mono-and polycrystalline silicon. In this combined micromachining technology, the polysilicon film is the main structural material and it is used to build the mechanical actuators.

A nanowire (NW) device in parallel with a normal nMOSFET is fabricated with a poly-Si planar CMOS process on (5 5 12)Si. With a unit cell of 5.35 nm, this plane has the largest stable atomically flat Si surface. When output current Isd flows from source S to drain D along <110>, the device has 15 positive spikes at integer multiples of 154 mV, all at 300K and zero magnetic field. Ids has only 9 positive and 2 negative spikes. The positive spikes in Isd and Ids are due to parabolic confinement of elongated q-dots in the NWs near D. Both Isd and Ids show missing spikes and onedimensional artificial atom behavior. The negative spikes appear to be Kronig-Penney effects on the NWs. The NWs and q-dots have estimated widths near 2 nm and Line Edge Roughness (LER) less than 0.1 nm due to the crystal-lattice precision of the surface. Perspective and IntroductionThere have recently been a number of discussions of the future of CMOS and other modern nanoelectronic devices when the smallest meaningful dimensions (SMDs) are reduced to the "single-digit" true nanometer scale below 10 nm. For example, significant attention has been paid to spin-based logic which predicts that up and down spins can move in an electric field in opposite directions along opposite edges of a nanowire, sometimes even in a zero magnetic field (1). A related example involves the storage and dissociation of excitons in parallel chains of semiconducting polymers (2). Quantum dots (q-dots) also have a wide range of highly unusual properties (3). Another surprising effect involves a circuit that results in the violation of Kirchoff's laws where series resistors no longer add to each other (4). All of the above are generally only observed within a few degrees of absolute zero, and they typically occur only when one or more of the device dimensions are of the same magnitude as interatomic distances or the electron wavelength (5). We discuss here a room temperature nanowire device made with standard CMOS technology that has several perplexing anomalies that appear to fall into one or more of the above categories. However, in this work we limit our working model to well known quantum effects involving parabolic confinement of elongated Si q-dots (6), the electron reflected branch of the Kronig-Penney model (6), and evidence for the existence of one dimensional (1D) or two dimensional (2D) artificial atoms (7).

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