Beyond CMOS Technology Sequence

As already mentioned, guessing beyond CMOS would be like playing roulette at your favorite casino. Figure 10.3 shows a possible roadmap that includes alternative materials such as III V semiconductors and new nanostructures such as carbon nanotubes. However, organized work has begun in surveying the landscape beyond CMOS. Some of the great minds in this area are collaborating with the SRC as part of a task force working on emerging research devices. They have composed a taxonomy of emerging...

Chemical Vapor Deposition

CVD is a popular technique in the silicon integrated circuit (IC) manufacturing industry to grow a variety of metallic, semiconducting, and insulating thin films. Typical CVD relies on thermal generation of active radicals from a precursor gas that leads to the deposition of the desired elemental or compound film on a substrate. Sometimes, the same film can be grown at a much lower temperature by dissociating the precursor with the aid of highly energetic electrons in a glow discharge. In...

Partially Soluble Bicomponent Fibers

Ultrafine fibers also can be prepared using bicomponent fibers comprised of a desired polymer and a soluble polymer. The soluble polymer is then dissolved out of the composite fiber, leaving micro- or even nanofilaments of the other remaining insoluble polymer 14,79-81 . Islands-in-the-sea fibers are typically used in such approaches. These fibers are composed of numerous much smaller filaments, all completely separated from each other by the sea (matrix) of another polymer (Figure 21.7)....

Splittable Bicomponent Fibers

An alternative way to produce ultrafine fibers is splitting bicomponent (conjugate) fibers, which consist of two polymers having different chemical or physical properties. The splitting fiber technology was first developed commercially in Japan in the mid- to late 1960s for synthetic suede fabrics 74 . The production of microfibers or even nanofibers involves spinning and processing of the bicomponent fibers in the range from 2 to 4 denier per filament (20 to 40 im), after which the fibers are...

The Meltblowing Process

The concept of meltblowing was first demonstrated in 1954 by Van A. Wente, of the Naval Research Laboratories, who was interested in developing fine fibers to collect radioactive particles in the upper atmosphere to monitor worldwide testing of nuclear weapons. In this process, an extruder forced a molten polymer through a row of fine orifices directly into two converging high-velocity streams of heated air or other gas. It was claimed that fibers as small as 0.1 to 1 im can be formed by this...

A Matlab Codes

The MATLAB codes for the toy models can also be obtained at www.nanohub.purdue.edu. Toy model, one level Inputs (all in eV) E0 - 5 . 5 E f -5 gam1 0 .2 gam2 0.2 U 1 Constants (all MKS, except energy which is in eV) hbar 1.06e-34 q 1.6e-19 IE (2*q*q) hbar kT .025 Bias (calculate 101 voltage points in -4 4 range) nV 101 VV linspace(-4,4,nV) dV VV(2)-VV(1) N0 2 (1 + exp((E0-Ef) kT) ) for iV 1 nV Voltage loop UU 0 dU 1 V VV(iV) mu1 Ef-(V 2) mu2 Ef+(V 2) while dU> 1e-6 SCF E E0+UU f1 1...

Azobenzene Nanovalve

FIGURE 11.13 Azobenzene polypeptide utilized for light-driven single-molecule force measurements. AFM cantilever tip. Force-extension curves of the polypeptide molecules when the molecule is switched between the trans-dominated photostationary state at 420 nm and the 's-dominated photostationary state at 365 nm are in accordance with the expected shortening of the polymer chain. The mechanical work done by the photoisomerization of the polypeptide was measured through a full work cycle. First a...

Composite Nanofibers via Electrospinning

Composite nanofibers are attracting considerable attention in areas such as wound dressings, medical prostheses, drug delivery, protective clothing, and catalysis, through the incorporation of functional nanoparticles into the polymer matrix during the electrospinning process. For example, electrospun FIGURE 21.10 TEM image of magnetic nanoparticles from a water-based commercial ferrofluid. titania nanofibers loaded with gold nanoparticles and carbon nanotubes for use in photocatalysis and...