Computer integrated manufacturing [semiconductor processing]

It is noted that, in computer-integrated manufacturing (CIM), there are many advantages to collecting and managing data from front-end and back-end operations in a logically integrated structured database. When this is done, correlations between elements in these data sets can be used to localize and quickly diagnose problems that reduce productivity. A simple and flexible system architecture suitable for this application is described. This CIM architecture is a two-level one. The lowest level includes the embedded controllers that provide real-time control of semiconductor analysis and fabrication equipment. Personal computers used as equipment controllers or for other tasks are included within this first level. The second level comprises a distributed network of computer workstations, file servers, and compute servers linked by a common distributed relational DBMS. Some workstations may be diskless; others may include local disks of varying sizes. A high-speed local area network (10 to 100 Mb/s) provides communications among processors at this level