Abstract
A measuring method for thin film thickness plated on partial baseplate surface comprising: (a) setting one X, Y, Z coordinate original point on baseplate surface plated with the thin film; (b) generating one specific polarized light to straight edge of the thin film; (c) detecting specific polarized intensity scattered from straight edge of the thin film; (d) adjusting the specific polarized light and the scattered light intensity; (e) by Bichel-Bailey method getting one 4x4 matrix S called Mueller matrix; (f) normalizing all elements of Mueller matrix; (g) by thin film with known thickness repeating step (a) to step (f) to get relation graph with normalizing elements S12*, S21*, S22*, S33*, S34*, S43* and S44* versus thin film thickness; (h) by thin film with unknown thickness repeating step (a) to step (f) to get values of normalizing elements S12*, S21*, S22*, S33*, S34*, S43* and S44* versus thin film thickness; (i) selecting the only one commonly appeared thickness in step (h) as thickness of the unknown thickness.