ABSTRACT
Application of NEMS for developing high-efficiency telecom-munication systems is being addressed by several groups.5,10-22 Nanomechanical resonators are called to replace quartz crystals in the field of the RF communications due to their capability to be fabricated with standard integrated circuit (IC) process. The reason derives from the high(er) frequencies that they can achieve and the small area that they would require. The primary building blocks for any telecommunication system are oscillators. Self-sustaining oscillator with feedback can be implemented by employing a NEMS resonator as the frequency determining-element for the feedback oscillator. Some other relevant examples of the use of NEMS for telecommunications are the mechanical implementation of filters23 and frequency convertors.15As it applies for testing or establishing of device production changes, when developing novel nanofabrication methods, the first phase is to realize discrete structures or devices. Once it has been demonstrated that one single nanostructure or nanodevice is useful by itself, the next stage is to optimize the fabrication method in order to improve its robustness and reliability, as well as the throughput, understood as the number of structures per unit time to be produced. However, most of the time, nanostructure and nanodevices are not useful by themselves, alone. To get a functional system, it is needed to have a set of devices interconnected or working simultaneously, or to combine them with other structures and devices, eventually of different critical
size. In the latter case, it is requisite to combine and adapt different fabrication methods.The highest level of system complexity, and in turn of functionality, can be achieved by the combination of nanodevices with microelectronic circuits. Its most straightforward example is to use a nanodevice for the sensing purposes and interface it to a microelectronic circuit for the signal conditioning and amplification. This approach has been followed during many years in microsystem technology, and it is now being expanded to incorporate novel nanotechnology concepts.
