27. A particle is only on one side connected by a tunnel junction. On this side electrons can tunnel in and out. Imagine for instance a metal particle embedded in oxide, as shown The top oxide layer is thin enough for electrons to tunnel through. To transfer one electron onto the particle, the Coulomb energy EC = e2/2C, where C is the particles capacitance, is required. Neglecting thermal and other forms of energy, the only energy source available is the bias voltage Vb. As long as the bias voltage is small enough, smaller than a threshold Vth = e/C, no electron can tunnel, because not enough energy is available to charge the island. This behavior is called the Coulomb blockade . Raising the bias voltage will populate the particle with one, then two and so on electrons, leading to a staircase-like characteristic.
28. Coulomb oscillations and Coulomb blockade, only matter, if the Coulomb energy is bigger than the thermal energy. The necessary condition is where kB is Boltzmann's constant and T is the absolute temperature. The capacitance C has to be smaller than 12 aF for the observation of charging effects at the temperature of liquid nitrogen and smaller than 3 aF for charging effects to appear at room temperature. Quantum fluctuations of the number of electrons on an island must be negligible. Electrons need to be well localized on the islands. The `transparency' of a tunnel junction is given by its tunnel resistance RT which must fulfill the following condition for observing discrete charging effects where h is Planck's constant. This should be understood as an order-of-magnitude measure, rather than an exact threshold.
33. In an embedded system design, the attention is always focussed in the reduction of size,cost and power loss. Power consumption crisis were historically solved by moving to new technologies that decrease energy per operation In the 1960s vacuum tubes were replaced with semi conductor devices.In the 1990s CMOS replaced BJTs.
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36. SETs have the ability to efficiently implement functions that are inefficient using BJTs,CMOS etc The Cyclic I-V curve of SET makes the implementation of complex functions easier
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40. SPICE includes these analyses: AC analysis (linear small-signal frequency domain analysis) DC analysis (nonlinear quiescent point calculation) DC transfer curve analysis Noise analysis Transfer function Transient analysis (time-domain large-signal solution of nonlinear differential algebraic equations)
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