Reliability of a component or a system can be considered a design parameter, but, in fact, the intrinsic design reliability may not be realized because of manufacturing defects or misapplication. Thus, the definition of reliability is the probability that a device or system will perform a specified function for a specified period of time under a specific set of conditions. The conditions may also include required maintenance procedures. The first chapter in this section expands on the definitional issues of reliability, including parts and systems modeling, reliability theory and practice, and failure analysis and prediction techniques. Chapter 3.2 discusses very high reliability techniques developed for military and aerospace applications. The special issues involved in semiconductor component reliability are covered in Chap. 3.3.

In a completely new chapter (3.4) the exceptional considerations needed in predicting reliability when using electromechanical and microelectromechanical devices are treated. Although many of the stress-strength relationships applicable to conventional electromechanical components apply to microelectro-mechanical devices, too, differences in the reliability of microelectromechanial systems (MEMS) that may be related to materials, geometries, and failure mechanisms are still under study. Thus far there is a limited amount of parts failure data available; it will be augmented as MEMS technologies mature and as the application of MEMS broadens. Additional material related to this chapter...