PROCESS-CONTROL IN SEMICONDUCTOR MANUFACTURING

Semiconductor processing requirements are creating a need for better equipment capabilities with respect to process control. The goal of this paper is to propose the required capabilities and suggest what issues must be addressed in order for the equipment to have these capabilities. This paper will focus on the why and how of control, such as the components and various implementation forms of controllers, rather than specific algorithms. The major concepts of process control will be presented, such as multivariable control systems. The basic requirements for control to be possible will also be introduced. The role of metrology as pertaining to process control methods will be presented. The involvement of the process engineer with respect to control will be highlighted so that the proposed requirements for the flexibility and configurability of the equipment control system will be better understood. Examples of process control applications in semiconductor manufacturing will assist in explaining the concepts introduced in this paper. (C) 1995 American Vacuum Society.