Recently a great interest has risen on the development of interfaces between molecular systems and traditional electronic or optoelectronic devices. Such devices can have a great number of applications, with the only limitation residing in the ability to obtain reproducible and controllable preparations. The use of a standard substrate, such as unoxidized crystalline silicon, offers many advantages, allowing the combination of the existing semiconductor production processes with the biological deposition. This is an extremely fertile field and has a number of promising applications such as...