Since the invention of the bipolar transistor in 1947, there has been unprecedented growth of the semiconductor industry. In the last 20 years or so by far the strongest growth area of semiconductor industry has been in silicon Very Large Scale Intergration (VLSI) technology. The sustained growth in VLSI technology is fueled by continued shrinking of transistors to ever smaller dimensions. The benefits of miniaturization - higher packing densities, higher circuits speeds, and lower power dissipation-have been key in the evolutionary process leading to todays computers and communication...