StraDex t

StraDex t is a thin film measuring instrument for all SemDex metrology tools. The technology behind is called reflectometry.

It measures vertical distances down to 5 nm with high accuracy and precision between two or more different optically transparent materials with wavelength from 200 nm to 1.050 nm.

Such materials are polymers, photoresists, dioxides, nitrides and the common materials used in semiconductor processes like Silicon, Silicon Carbide, Sapphire, Gallium Arsenide and others.

The measuring instrument records 1.000 thousand measurement points in a second and combined with the movement of the wafer stage it can generate full wafer data maps within one minute.

StraDex t is usually placed above and underneath the wafer to measure distances even of opaque wafers or wafers with backside roughness.
Matching measuring instruments can be placed in addition on top and bottom side of the stage to extend the range of applications to be covered by only one SemDex metrology tool.

Typical metrology applications are: thin film thickness and thin film stack thickness, descum process control and ion beam trimming.