In the past 46 years, Intel Moore observed an exponential doubling in the number of transistors in every 18
months through the size reduction of individual transistor components since 1965. In this paper, we are exploring the
nanotechnology impact upon the Law. Since we cannot break down the atomic size barrier, the fact implies a
fundamental size limit at the atomic or Nanotechnology scale. This means, no more simple 18 month doubling as in
Moore's Law, but other forms of transistor doubling may happen at a different slope in new directions. We are
particularly interested in the Nano enhancement area. (i) 3-D: If the progress in shrinking the in-plane dimensions (2D)
is to slow down, vertical integration (3D) can help increasing the areal device transistor density and keep us on the
modified Moore's Law curve including the 3rd dimension. As the devices continue to shrink further into the 20 to 30 nm
range, the consideration of thermal properties and transport in such nanoscale devices becomes increasingly important.
(ii) Carbon Computing: Instead of traditional Transistors, the other types of transistors material are rapidly developed in
Laboratories Worldwide, e.g. IBM Spintronics bandgap material and Samsung Nano-storage material, HD display
Nanotechnology, which are modifying the classical Moore's Law. We shall consider the overall limitation of phonon
engineering, fundamental information unit 'Qubyte' in quantum computing, Nano/Micro Electrical Mechanical System
(NEMS), Carbon NanoTubes (CNTs), single layer Graphemes, single strip Nano-Ribbons, etc., and their variable degree
of fabrication maturities for the computing and information processing applications.
We investigated the effects of doping on the photovoltaic efficiency in a GaAs reference cell,
and in undoped, n-doped, and p-doped InAs/GaAs quantum-dot (QD) solar cells. We found that
the photovoltaic efficiency of the undoped QD solar cell is almost the same as that of the
reference cell. However, the efficiency improves monotonically with increasing inter-dot ndoping,
while p-doping deteriorates the photovoltaic conversion. We observed a 50 % increase in
photovoltaic efficiency in the device n-doped to provide approximately six electrons per dot as
compared with the undoped QD cell. In this QD solar cell, the short circuit current density
increases to 24.30 mA/cm2 compared with 15.07 mA/cm2 in the undoped QD solar cell without
deterioration of the open circuit voltage. To identify the physical mechanisms that provide this
improvement, we investigated the spectral characteristics of the photovoltaic response and
photoluminescence of our QD solar cells. We found that the electron capture into QDs is
substantially faster than the hole capture, which leads to an accumulation of electrons in QDs.
The electrons trapped in dots enhance IR transitions. The built-in-dot electron charge together
with charged dopants outside the dots creates potential barriers, which suppress the fast electron
capture processes and at the larger scale form a potential profile which precludes degradation of
the open circuit voltage. All of these factors lead to the enhanced harvesting of IR energy and a
radical improvement of the QD solar cell efficiency. Higher efficiencies are anticipated with
further increase of doping level and at higher radiation intensity. This makes the QD solar cells
promising candidates for use with concentrators of solar radiation.
For EOIR nanotechnology sensors, we elucidated the quantum mechanical nature of the Einstein photoelectric effect in terms of a field-effect transistor (FET) made of Carbon NanoTube (CNT) semiconductors. Consequently, we discovered a surprising low-pass band gap property, as opposed to the traditional sharp band-pass band-gaps. In other words, the minimum amount of photon energy shining in the middle of CNT is necessary to excite the semiconductor CNT electrons. The conduction electron will spiral in a steady over the surface to minimize the collision recombination when travelling from the cathode end to the anode end by the asymmetric semiconductor-metal (using Pd or Al) Schottky interface effect for read out.
We describe a smart surveillance strategy for handling novelty changes. Current sensors seem to keep all, redundant
or not. The Human Visual System's Hubel-Wiesel (wavelet) edge detection mechanism pays attention to changes in
movement, which naturally produce organized sparseness because a stagnant edge is not reported to the brain's
visual cortex by retinal neurons. Sparseness is defined as an ordered set of ones (movement or not) relative to zeros
that could be pseudo-orthogonal among themselves; then suited for fault tolerant storage and retrieval by means of
Associative Memory (AM). The firing is sparse at the change locations. Unlike purely random sparse masks
adopted in medical Compressive Sensing, these organized ones have an additional benefit of using the image
changes to make retrievable graphical indexes. We coined this organized sparseness as Compressive Sampling;
sensing but skipping over redundancy without altering the original image. Thus, we turn illustrate with video the
survival tactics which animals that roam the Earth use daily. They acquire nothing but the space-time changes that
are important to satisfy specific prey-predator relationships. We have noticed a similarity between the mathematical
Compressive Sensing and this biological mechanism used for survival. We have designed a hardware
implementation of the Human Visual System's Compressive Sampling scheme. To speed up further, our mixedsignal
circuit design of frame differencing is built in on-chip processing hardware. A CMOS trans-conductance
amplifier is designed here to generate a linear current output using a pair of differential input voltages from 2
photon detectors for change detection---one for the previous value and the other the subsequent value, ("write" synaptic weight by Hebbian outer products; "read" by inner product & pt. NL threshold) to localize and track the
We report the substantial increase in power efficiency in InAs/GaAs quantum dot (QD) solar cells due to n-doping of the inter-dot space in p+-δ-n+ structures and investigate the physical mechanisms that provide this significant improvement. We have compared the GaAs reference cell to undoped, n-doped and p-doped QD solar cell structures and found that the short circuit current, JSC, of the undoped QD solar cell is comparable to that of the GaAs reference cell. On the other hand, while p-doping deteriorates the device performance, n-doping significantly increases JSC without degradation of the open circuit voltage, VOC. The photovoltaic device, n-doped to provide approximately six electrons per dot, demonstrates 60% increase in JSC, from 15.07 mA/cm2 to 24.30 mA/cm2. Strong increase in the photoresponse and JSC of the IR portion of the solar spectrum has been observed for the n-doped structures. From the photoluminescence data, the electron capture noticeably dominates over hole capture leading to an accumulation of electrons in the dots. We have observed that QDs with built-in charge (Q-BIC) enhances harvesting of IR energy, suppresses the fast electron capture process, and stabilizes the open circuit voltage. All of these factors lead to a significant improvement of the cell efficiency.
A major problem of current silicon thin film solar cells lies in low carrier collection efficiency due to short carrier diffusion length. Instead of improving the collection efficiency in a relatively thick solar cell, increasing light absorption while still keeping the active layer thin is an alternative solution. Absorption enhancement in a thin film Si solar cell by incorporating a two-dimensional periodic metallic nanopattern was investigated using three-dimensional finite element analysis. By studying the enhancement effect brought by different materials, dimensions, coverage, and dielectric environments of the metal nanopattern, we found that absorption enhancement occurs at wavelength range outside surface plasmons resonance of the nanostructures. The exploitation of the nanostructures also enhances the Fabry-Perot resonance in the active layer. It plays an important role in optimizing the absorption of the solar cell.
Inspired by Asian rice-paddy and Firefighter spiraling steps staircase, we employ a nano-manipulator augmented with CAD as a nano-robot water-buffalo, promised to improve by an order of the magnitude the pioneer work of GE Solar voltaic cell (SVC) made of one Carbon NanoTube (CNT) enjoyed QECNT~5%. Our CNT was made of the semiconductor at NIR wavelength EBG= 1.107 eV which can absorb any photon whose wavelength λ ≤ λNIR =1.11 μm. This EBG is chosen due to the cutoff of Pb-Crown
glass which happened put us in the equal amount of solar energy spectrum as silicon p-n junction SVC. Nevertheless, the exceeding of the Shockley and Queisser efficiency limit 30% might be due to the fact that we have much compact one-dimensional building block
CNT of a tiny diameter 0.66 nm. It allows us to construct 3D structure, called volume pixel, "voxel," in a much efficient spiraling steps staircase fashion to capture the solar
spectral energy spreading naturally by a simple focusing lens without occlusion. For real-estate premium applications, in Space or Ocean, we designed a volume pixel (Voxel)
housing a stack of 16 CNTs steps spiraling 22° each like the fire house staircase occupying the height of 16 x dCNT =16 x 0.66nm= 10.56 nm and covering over 360°. The total SVC had the size 2x2 meter2, consisting of 100×100 lenslet array. Each lens was
made of Pb-Crown glass which was inexpensive simple spherical lens having the
diameter of Dlens=2 cm and F#=0.7. It can focus the sunlight a millionth times stronger in
a smallest possible focal spot size, λYellow=0.635 μm< λMax photons <λRed=0.73 μm, where the largest number of solar photons, 68%, according to the Plank radiation spectrum at 6000°K and the Lord Rayleigh diffraction limit. The solar panel seals individually such
an array of 3D cavities of SVC enjoying theoretically from the UV 12% (wasted in passing through) visible 68% to the infrared 20% at a total of 16x5%~80% total QECNT per cell. The solar panel is made of light-weight carbon composite tolerating about 20% inactive fill factor and 10% dead pixels.