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Single-walled carbon nanotubes (SWNT) are grown by a plasma enhanced chemical vapor deposition (PECVD) method at 600 °C. The nanotubes are of high quality as characterized by microscopy, Raman spectroscopy, and electrical transport measurements. High performance field effect transistors are obtained with the PECVD nanotubes. Interestingly, electrical(More)
An oxygen-assisted hydrocarbon chemical vapor deposition method is developed to afford large-scale, highly reproducible, ultra-high-yield growth of vertical single-walled carbon nanotubes (V-SWNTs). It is revealed that reactive hydrogen species, inevitable in hydrocarbon-based growth, are damaging to the formation of sp(2)-like SWNTs in a diameter-dependent(More)
We fabricate and optically characterize germanium microdisks formed out of epitaxial germanium grown on silicon. Resonators coupled to fiber tapers display clear whispering gallery modes in transmission and photoluminescence with quality factors limited by germanium's material absorption. Continuous wave pumping of the cavities resulted in a dominant(More)
Probe-based memory devices using ferroelectric media have the potential to achieve ultrahigh data-storage densities under high write-read speeds. However, the high-speed scanning operations over a device lifetime of 5-10 years, which corresponds to a probe tip sliding distance of 5-10 km, can cause the probe tip to mechanically wear, critically affecting(More)
We electrically and optically characterize a germanium resonator diode on silicon fabricated by integrating a germanium light emitting diode with a microdisk cavity. Diode current-voltage characteristics show a low ideality factor and a high on/off ratio. The optical transmission of the resonator features whispering gallery modes with quality factors of a(More)
InxGa1-xSb is an attractive candidate for high performance III-V p-metal-oxide-semiconductor field effect transistors (pMOSFETs) due to its high bulk hole mobility that can be further enhanced with the use of strain. We fabricate and study InxGa1 xSb-channel pMOSFETs with atomic layer deposition Al2O3 dielectric and self-aligned source/drain formed by ion(More)
Joule-heating induced conductance-switching is studied in VO2 , a Mott insulator. Complementary in situ techniques including optical characterization, blackbody microscopy, scanning transmission X-ray microscopy (STXM) and numerical simulations are used. Abrupt redistribution in local temperature is shown to occur upon conductance-switching along with a(More)
Precise electrical manipulation of nanoscale defects such as vacancy nano-filaments is highly desired for the multi-level control of ReRAM. In this paper we present a systematic investigation on the pulse-train operation scheme for reliable multi-level control of conductive filament evolution. By applying the pulse-train scheme to a 3 bit per cell HfO2(More)
We report the room temperature electroluminescence (EL) at 1.6 microm of a Ge n+/p light emitting diode on a Si substrate. Unlike normal electrically pumped devices, this device shows a super linear luminescence enhancement at high current. By comparing different n type doping concentrations, we observe that a higher concentration is required to achieve(More)
For single-walled carbon nanotube (SWNT) field effect transistors, vertical scaling of high kappa dielectrics by atomic layer deposition (ALD) currently stands at approximately 8 nm with a subthreshold swing S approximately 70-90 mV/decade at room temperature. ALD on as-grown pristine SWNTs is incapable of producing a uniform and conformal dielectric layer(More)