Description FR-Thermal is a compact optical tool for the monitoring of the thickness and optical properties changes of polymer or photoresist films during controlled thermal treatment (heating / cooling). By using FR-Thermal and the especially developed algorithms provided in FR-Monitor, physicochemical properties such as: glass transition temperature (Tg), degradation temperature (Td) of polymer films are evaluated for a wide film thickness range (<10nm - 100μm).

FR-Thermal tool is based on FR-Basic platform with the addition of a computer controlled heating/cooling unit and exploits White Light Reflectance Spectroscopy (WLRS) for real time measurement of film thickness and refractive index. FR-Thermal is fully controlled by FR-Monitor which include and extended materials database.

The entire system (hardware – software) is shipped ready for measurements and can be easily used by anyone with basic computer skills without any deep knowledge of optics. The only additional part needed is a computer with one free USB ports running Windows XP/Vista/7 32/64 bit. The film thickness and optical constants are calculated in real time while the physicochemical properties are determined after the completion of the measurements.

Tight control over the heating and cooling rates allows for in depth study of the polymer film properties. FR-Thermal is also ideal for many other thermal studies such as film thermal ablation, temperature dependent optical properties changes, Post Apply Bake, Post Exposure Bake thickness loss in lithography etc.

FR-Thermal can handle layer stacks of up to four layers (environment and substrate are additional layers) and two parameters may be calculated e.g. the thicknesses of two films or the thickness and the optical constants of one film.FR-Thermal tool has been successfully applied for the calculation of the thermal properties of various polymer films as well as on the evaluation of the effect of thermal treatment on the lithographic properties of several photoresist films over totally reflecting substrates (Si wafer).

 

Fig. 1: FR-Thermal tool schematic showing the reflection probe and the heating unit where the sample is placed	Fig. 2: Glass Transition Temperature of a PMMA film, using FR-Thermal tool