The invention of semiconductor devices is a fairly recent one,
considering classical time scales in human life. The bipolar transistor
was announced in 1947, and the MOS transistor, in a practically usable
manner, was demonstrated in 1960. From these beginnings the
semiconductor device field has grown rapidly. The first integrated
circuits, which contained just a few devices, became commercially
available in the early 1960s. Immediately thereafter an evolution has
taken place so that today, less than 25 years later, the manufacture of
integrated circuits with over 400.000 devices per single chip is
possible. Coincident with the growth in semiconductor device
development, the literature concerning semiconductor device and
technology issues has literally exploded. In the last decade about
50.000 papers have been published on these subjects. The advent of so
called Very-Large-Scale-Integration (VLSI) has certainly revealed the
need for a better understanding of basic device behavior. The
miniaturization of the single transistor, which is the major
prerequisite for VLSI, nearly led to a breakdown of the classical models
of semiconductor devices.