E. Gusev et al. (eds.), Advanced Materials and Technologies for Micro/Nano-Devices, 249 Sensors and Actuators, DOI 10.1007/978-90-481-3807-4_20, © Springer Science + Business Media B.V. 2010 SMART SENSORS: ADVANTAGES AND PITFALLS Abstract have been many examples of success stories for simple silicon sensors, such as the Hall plate and photo-diode. These have found mass-market applications. The development of micromachining techniques brought pressure sensors and accelero- meters into the market and later the gyroscope. These have also achieved mass- market use a simple sensor with external electronics or read-out electronics in the same package (system-in-a-package). However, there are also many examples of fully integrated sensors (smart sensors) where the whole system is integrated into a single chip. If the application and the device technology permit this, there can be many advantages. A broader look at sensors shows a wealth of integrated devices. The critical issues are reliability and packaging if these devices are to find the applications. A number of silicon sensors and actuators have shown great commer- cial success, but still many more have to find their way out of the laboratory. This paper will examine the development of the technologies, some of the success stories and the opportunities for integrated Microsystems as well as the pitfalls. Keywords: Smart sensors, silicon processing, integration. 1. Introduction In the cases where additional process steps are required they can be performed as pre-processing, integrated processing or post-processing. All have their advantages and disadvantages and have to be considered in each case. Early silicon sensors were non-integrated and contained external read-out electronics. The simplest solution, when integrating sensors, is when the sensor can use layers already used in the electronics. Magnetic sensors based on Hall plates are good examples of these, although issues such as exposure of the electronics to the magnetic field need to be considered. However, many examples can be found where special processing has been added to standard processing to make integrated devices. Tel +31-15-2784729, e-mail: p.j.french@tudelft.nl market. The remaining issue is how far to integrate. Many of the devices on the EI-EWI-DIMES, TUDelft, Mekelweg 4, 2628CD Delft, The Netherlands For almost 50 years, silicon sensors have been on the market. There PADDY JAMES FRENCH