ABSTRACT
The microelectronics industry is driven, as with other industries, by the need to remain financially viable. In the area of microelectronics circuitry, profitability has been connected to the reduction in size of the elements that make up these circuits. There are two reasons for this. First, the future success of these industries depends on their continuing to be at the cutting edge of the technology. For example, if the trend in miniaturization halts, the fabrication technology will stabilize and it would then become possible to fabricate microelectronics circuits without the need for a highly skilled and educated work force. Second, lower unit costs (e.g. the cost per byte of memory) are seen to be possible through increased miniaturization and integration. These trends have the added benefits of leading to faster speeds and lower energy (i.e. lower cost) per unit operation. Since the invention of the integrated circuit (IC), the minimum feature size of individual structures in the circuits has halved every five years or so. This trend was noted in 1975 by Moore [1] and the 'Moore curve' (as it is often called), shown in figure 20.1, has proved to be a remarkably accurate prediction of progress over the intervening two decades.
