The double gate transistor is a promising device applicable to deep sub-micron design due to its inherent resistance to
short-channel effects and superior subthreshold performance. Using both TCAD and SPICE circuit simulation, it is
shown that the characteristics of fully depleted dual-gate thin-body Schottky barrier silicon transistors will not only
uncouple the conflicting requirements of high performance and low standby power in digital logic, but will also allow
the development of a locally-connected reconfigurable computing mesh. The magnitude of the threshold shift effect will
scale with device dimensions and will remain compatible with oxide reliability constraints. A field-programmable
architecture based on the double gate transistor is described in which the operating point of the circuit is biased via one
gate while the other gate is used to form the logic array, such that complex heterogeneous computing functions may be
developed from this homogeneous, mesh-connected organization.
Over the last few years, piezoelectric elements have gained popularity as a convenient and relatively inexpensive interface between the electrical and mechanical domains of power harvesting and vibration damping systems. Power harvesting is commonly performed by placing a bridge rectifier across the piezoelectric element and feeding the output into a capacitor and matched load, in much the same manner as used in a standard power supply circuit. However, the overall efficiency of the electrical power harvesting system using this approach can be quite low. Therefore, there is a continued search for circuit architectures and techniques to enhance the efficiency and performance of such systems. It is shown that using piezoelectric devices for electrical power harvesting is closely related to vibration damping using the same devices. This paper proposes that focusing on the reflected mechanical power could produce more efficient systems than focusing on electrical power transfer alone. In exploring this proposition an attempt was made to identify important parameters in the design of such systems. This exploration has demonstrated the importance of maximizing the voltage across the piezoelectric element as the primary means of maximizing the reflected mechanical power. Complexity and cost are often issues when operating piezoelectric devices at high voltages, which led to the development of a relatively simple charge polarity reversal mechanism. Such a mechanism has been demonstrated to improve the efficiency of energy harvesting and/or vibration damping. Simulation of this concept shows a substantial improvement over the bridge rectifier concept. Whilst the magnitude of improvement is dependent on how high the voltage across the piezoelectric element can be raised, the scenario shown in detail gives an improvement of approximately two orders of magnitude.