Ahmad Bayat and Colin G. Gordon
Vibration-sensitive instruments are by no means a new phenomenon. Galileo reportedly experienced vibration problems with his telescope. In the context of the microelectronics industry, tool sensitivity to vibration and noise is an item of particular concern since they can substantially affect product yield. Also, of course, fab cleanrooms are very energetic in terms of installed mechanical systems. These systems have a propensity to generate vibration and noise.
Early on in our work with the microelectronics industry, there were no vibration criteria that one could use as a basis for facility design - nor were there even accepted methods for measuring vibration performance. Few, if any, tool makers had developed accurate performance requirements for their tools. Even at the present time, significant numbers of tools lack reliable vibration and acoustic specifications.
Because of the early lack of vibration standards and guidelines for microelectronics facilities, a set of criterion curves, commonly called the generic vibration criterion (VC) curves, were developed. These curves - now widely used throughout the world - are described in Reference 1. We have extracted Figure 1 and Table 1 from Reference 1, depicting the VC curves and their relationship to line width or feature size.
In this paper, we examine the evolution of vibration considerations in fab design. We discuss the present status, and elaborate on future needs, with specific reference to 300 mm conversion.
Reprinted from Proceedings of the ICCCS 14th International Symposium on Contamination Control, Institute of Environmental Sciences and Technology, Phoenix, Arizona, April 26-May 1, 1998, pp. 139-143