TABLE OF CONTENTS Historically, the development of thin layers began early and has prospered greatly. Nevertheless, it is afflicted with some problems which will have to be dealt with in future research. In the following, some examples are briefly described:
The scaling and reduction of all geometrical sizes of electronic devices has also lead to the application of thinner gate oxide. It has to be considered, though, that a substantial aspect of gate oxide based MOS technique is based on its high isolation ability. However, when thickness falls short of 4 nm, tunneling currents removing the blocking capability come into action. The only remedy so far consists of accepting these tunneling currents and simply refreshing the signals. So far it is an unsettled question whether more stable dielectrics can be developed.
The same question refers to the operability of image-delivering CCD devices on the basis of isolation oxides. In this case the signal (the accumulated charge) can flow over the oxide as tunneling current. Thus, apparently the necessary refreshment times are increased but the signal is nonlinearly falsified.
When dealing with thinner oxides, the above field eventually increases. Effects such as oxide charge trapping and associated bias point shifts can occur then. Current blocking mechanisms such as Coulomb blockade, telegraph noise become apparent among other things.
Contradictory demands are made concerning the desired size of the dielectric constants of insulators. On the one hand, capacitance values become increasingly small by reducing dimension. Thus, the desire for a high...
