Run by run (generalized SPC) control of semiconductor processes on the production floor

Multiple linear response surface methodology coupled with run by run (generalized SPC) control has been applied at Delco Electronics to a high volume production epitaxy deposition process. This resulted in nearly a 1.8× improvement in process capability for thickness control. This was achieved by interfacing an IBM compatible 486 computer to Gemini II epi reactors, translating Sun workstation Matlab script code from the Massachusetts Institute of Technology into PC compatible Matlab script code, and combining this with the InTouch man machine interface (MMI) software package from Wonderware, Inc. This paper is a case study of our experience at implementing this on the production floor. We discuss the general nature of the process to show why this methodology is relatively easy to apply. Operator training was simplified, data acquisition capability was added, new enhanced modes of operation were implemented, and enhanced capability for more advanced processes is possible on equipment that did not originally provide these features