The international market is very competitive for high-tech manufacturers to day. Achieving competitive quality and reliability for products requires leader ship from the top, good management practices, effective and efficient operation and maintenance systems, and use of appropriate up-to-date engineering de sign tools and methods. Furthermore, manufacturing yield and reliability are interrelated. Manufacturing yield depends on the number of defects found dur ing both the manufacturing process and the warranty period, which in turn determines the reliability. the production of microelectronics has evolved into Since the early 1970’s, one of the world’s largest manufacturing industries. As a result, an important agenda is the study of reliability issues in fabricating microelectronic products and consequently the systems that employ these products, particularly, the new generation of microelectronics. Such an agenda should include: * the economic impact of employing the microelectronics fabricated by in dustry, * a study of the relationship between reliability and yield, * the progression toward miniaturization and higher reliability, and * the correctness and complexity of new system designs, which include a very significant portion of software.