The Importance of CTE in Multi-Layer Registration and Improved Measurement Methods

摘要

Precise measurements of thermal expansion properties on production-size laminates, innerlayers and re-laminated circuit boards can be used to improve our understanding of multi-layer registration problems, better characterize materials and formulate artwork compensation factors. Because the laminate CTE is not constant over the re-lamination temperature range, it may be desirable to use the total thermal expansion instead of the CTE to characterize these materials. For example, the inclusion of thermal expansion values in semi-empirical and/or data-based expert systems should greatly improve artwork compensation prediction capability. The laminate / innerlayer expansion displays provide a new way to visualize in-plane laminate and inner layer movement as a function of temperature. It provides not only a new way to characterize laminates, but also a means to experiment with the fundamental influences of glass geometry, resin content, circuit board construction, lamination processes, residual stress reduction and innerlayer circuitry and border patterns.